vision

Review
A Systematic Review of Clinical Practice Guidelines for
Cataract: Evidence to Support the Development of the WHO
Package of Eye Care Interventions
Justine H. Zhang 1,2, * , Jacqueline Ramke 1,3, * , Chan Ning Lee 1,4 , Iris Gordon 1 , Sare Safi 5,6 ,
Gareth Lingham 7 , Jennifer R. Evans 1,8 and Stuart Keel 9

1 International Centre for Eye Health, London School of Hygiene and Tropical Medicine,
London WC1E 7HT, UK; channing.lee@doctors.org.uk (C.N.L.); iris.gordon@lshtm.ac.uk (I.G.);
jennifer.evans@lshtm.ac.uk (J.R.E.)
2 Royal Free Hospital, London NW3 2QG, UK
3 School of Optometry and Vision Science, University of Auckland, Auckland 1142, New Zealand
4 St Paul’s Eye Unit, Royal Liverpool University Hospital, Liverpool L7 8XP, UK
5 Ophthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti
University of Medical Sciences, Tehran 16666-73111, Iran; saresafi.s@gmail.com
6 WHO Collaborating Centre for the Eye Care and Prevention of Blindness, Tehran 16666-73111, Iran
7 Centre for Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia,
Perth 6009, Australia; garethlingham@lei.org.au
8 Centre for Public Health, Queen’s University Belfast, Belfast BT7 1NN, UK
9 Vision and Blindness Prevention Programme, World Health Organization, 1211 Geneva, Switzerland;
keels@who.int
* Correspondence: justine.zhang@lshtm.ac.uk (J.H.Z.); jacqueline.ramke@lshtm.ac.uk (J.R.)

Abstract: The World Health Organization (WHO) is developing a Package of Eye Care Interventions
(PECI) to facilitate the integration of eye care into Universal Health Coverage. This paper presents
Citation: Zhang, J.H.; Ramke, J.; Lee,
the results of a systematic review of clinical practice guidelines for cataract in adults, to help inform
C.N.; Gordon, I.; Safi, S.; Lingham, G.;
PECI development. We searched academic and guideline databases, and websites of professional
Evans, J.R.; Keel, S. A Systematic
associations, for guidelines published between January 2010 and April 2020. Guidelines were
Review of Clinical Practice
Guidelines for Cataract: Evidence to
excluded if there was commercial funding or unmanaged conflicts of interest. Quality appraisal
Support the Development of the was conducted using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool. We
WHO Package of Eye Care identified 3778 reports, 35 related to cataract guidelines, four of which met the inclusion criteria
Interventions. Vision 2022, 6, 36. (United Kingdom: 2, United States: 1, Iran: 1). The recommendations across the four guidelines
https://doi.org/10.3390/ covered pre-operative (43%), intra-operative (37%), and post-operative interventions (20%). Most
vision6020036 ‘strong’ recommendations were supported by good quality evidence. Differences in recommendations
Received: 19 April 2022
across guidelines may be attributable to time of publication or regional differences in surgical practice.
Accepted: 8 June 2022 Few guidelines met the quality criteria, and only three countries were represented. The results of this
Published: 20 June 2022 step of the PECI development process will inform subsequent phases for development of the WHO’s
package of evidence-based eye care interventions for cataract.
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
Keywords: cataract; clinical practice guidelines; eye care interventions
published maps and institutional affil-
iations.

1. Introduction
Copyright: © 2022 by the authors. In its inaugural World report on vision in 2019, the World Health Organization (WHO)
Licensee MDPI, Basel, Switzerland. recommended that eye care should be integrated into Universal Health Coverage (UHC) to
This article is an open access article improve access to eye care services and strengthen eye care in health systems globally [1].
distributed under the terms and In response to this recommendation, the WHO is developing a priority package of evidence-
conditions of the Creative Commons
based eye care interventions (PECI) in collaboration with Cochrane Eyes and Vision [2].
Attribution (CC BY) license (https://
The development of PECI is in four phases: (1) selection of eye conditions; (2) identification
creativecommons.org/licenses/by/
of evidence-based eye care interventions using systematic methods to identify and appraise
4.0/).

Vision 2022, 6, 36. https://doi.org/10.3390/vision6020036 https://www.mdpi.com/journal/vision

Vision 2022, 6, 36 2 of 23

Clinical Practice Guidelines (CPGs); (3) agreement on interventions, their service delivery
platforms, and the resources required for each intervention; (4) peer review. The PECI
will be widely disseminated as a resource for countries to plan and integrate eye care
interventions into eye care services across their population.
It was estimated that in 2020, 94 million people globally had moderate or severe vision
impairment (MSVI) or blindness due to cataract [3]. This treatable condition is the leading
cause of blindness globally, and the second leading cause of MSVI [3]. In 2021, the World
Health Assembly endorsed a resolution for all countries to increase their effective cataract
surgical coverage this decade, which will require improvements in both access to services
and the quality of those services [4–6].
Treatment of cataract generally only requires one operation to remove the cataract
and place an artificial lens into the eye, along with relatively short pre- and post-operative
assessments. Cataract surgery is safe and effective when delivered by competent teams in
enabling environments. Phacoemulsification surgery is the most widely used procedure in
high-income settings and has the best surgical outcome in terms of unaided vision; although,
in terms of best corrected vision, the surgical outcomes between phacoemulsification and
small incision cataract surgery (SICS) are similar [7,8]. SICS is faster and cheaper than
phacoemulsification, and thus is currently more widely used in low-income settings [9].
The cataract surgical rate of a country (the number of cataract operations performed
in one year, per million population) is correlated with economic indicators such as Gross
Domestic Product (GDP), with increased surgical output increasing with GDP [10]. This
suggests that delivery of cataract surgery is strongly dependent on resource availabil-
ity. Therefore, achieving UHC is likely to be highly dependent on improving resource
availability and access to high-quality cataract services in low- and middle-income settings.
This paper aims to present the results, including quality appraisal, of a systematic
review of CPGs for cataract in adults (Phase 2 of the PECI development process).

2. Materials and Methods

We followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses
(PRISMA) reporting guidelines (Supplementary Materials S1) [11]. The rationale and
methodology for the development of the PECI, including the systematic review of CPGs, is
presented and published in a separate paper [2].
Eligibility Criteria: We included CPGs relating to cataract, from any country, published
after 2010 in the English language. Full exclusion criteria for each stage of selection of the
CPGs are provided in Table 1.

Table 1. Exclusion criteria for screening of Clinical Practice Guidelines (CPGs).

Title and Abstract Screening Full Text Screening Quality Appraisal *

(1) The identified report was not
(1) The average score of the
a CPG
(1) There was commercial two investigators for items 4,
(2) The guideline was published
funding or unmanaged 7, 8, 12, or 22 was below 3.
before 2010
conflicts of interest (2) the sum of the average
(3) The guideline was not
(2) Absence of affiliation score of the two investigators
in English
of authors was less than 45 for items 4, 7,
(4) The guideline was not
8, 10, 12, 13, 15, 22, and 23.
developed for cataract
* Items and scores refer to the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool [12].

Information Sources and Search: Systematic literature searching of MEDLINE, Embase,

CINAHL, Global Health, Global Index Medicus was conducted by an experienced Cochrane
Eyes and Vision information specialist (IG) in April 2020. The full search strategy can be
found in Supplementary Materials S2. Where applicable, MeSH terms were used. We also
conducted a search of relevant CPGs in guideline databases and the websites of professional
ophthalmology and optometry associations (listed in Supplementary Materials S3).
Vision 2022, 6, 36 3 of 23

Selection of Sources of Evidence and Appraisal: Titles and abstracts were independently
screened by two investigators (GL/SS), with the aid of a web-based organization tool
(Abstrackr, available at: http://abstrackr.cebm.brown.edu, (accessed on 15 May 2022)).
Any conflicts were resolved by discussion between a WHO (SK) and Cochrane Eyes and
Vision (JE) representative.
Full texts were then independently screened by two investigators (JZ/JR and JZ/CNL).
Any conflicts were resolved by discussion; if the two investigators could not come to a
consensus, the conflict was resolved by discussion with a third investigator (SK).
Quality appraisal of CPGs was conducted independently by two investigators (JZ/JR)
using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool [12]. Specific
items in the AGREE II tool were used for the selection of CPGs, being those agreed by
researchers to be the most relevant to selecting high-quality CPGs in a previous WHO
package of interventions [13], and in accordance with the protocol [2] (items 4, 7, 8, 10, 12,
13, 15, 22 and 23; Table 2). Each item was scored on a 7-point Likert scale, from 1–7 (strongly
disagree to strongly agree), so the maximum possible total score for all 9 items was 63. If the
scores given by the two investigators differed by more than 2, the conflict was resolved by
discussion between the two investigators, or with a third investigator. CPGs were excluded
if: (1) the average score between the two investigators was less than 3 for items 4, 7, 12, or
22; or (2) the sum of the average score of the two investigators was less than 45 for items 4,
7, 8, 10, 12, 13, 15, 22, and 23.

Table 2. AGREE II tool items used for the selection of Clinical Practice Guidelines (CPGs).

AGREE II
Item Description
Item Number
The guideline development group includes individuals from all relevant
4
professional groups *
7 Systematic methods were used to search for evidence.
8 The criteria for selecting the evidence are clearly described.
10 The methods for formulating the recommendations are clearly described.
There is an explicit link between the recommendations and the
12
supporting evidence.
13 The guideline has been externally reviewed by experts prior to its publication.
15 The recommendations are specific and unambiguous.
The views of the funding body have not influenced the content of
22
the guideline.
Competing interests of guideline development group members have been
23
recorded and addressed.
* For this manuscript, relevant professional groups include ophthalmologists, optometrists, orthoptists, eye health
researchers, and other allied eye health professionals.

Data Charting and Data Items: Data were charted using a standardized form. Data from
each CPG were extracted by a single investigator (JZ) and verified by a second investigator
(JR). Any conflicts were resolved by discussion with a third investigator (SK). The following
data items were extracted:
1. Title of the CPG;
2. Sponsoring organization (if there was no organization, then the name of the first
author was extracted);
3. Publication year;
4. Title of the chapter to which the recommendation refers to;
5. Page number, title and numbering of the section in which the recommendation
is stated;
6. Intervention target;
7. Intervention category;
8. Intervention name;
9. Who usually provides the intervention;
10. Dosage or frequency of the intervention;
Vision 2022, 6, 36 4 of 23

11. The specific recommendation copied and pasted from the relevant paragraph in
the CPG;
12. Recommendation strength, and the name or description of the classification sys-
tem used;
13. Quality or level of evidence relating to the recommendation, and the name or descrip-
tion of the classification system used;
14. Any other remarks on the recommendation that the investigator believes to be relevant.
Synthesis of Results: Recommendations of eye care interventions were tabulated, and cat-
egorized into pre-operative, intra-operative, and post-operative recommendations. For each
intervention tabulated, the corresponding CPG(s) that recommended that intervention was
listed, alongside judgements on the quality of evidence and strength of recommendation.
As the CPGs used different frameworks for assessing the quality of evidence and
strength of recommendation, we present the results narratively for each CPG.
Ethics and Dissemination: As this study only included freely available CPGs, ethics
approval was not sought. Results will be widely disseminated after the WHO, supported
by a Technical Advisory Group of experts, have agreed on which interventions should be
included in the final PECI (Phase 3), and after the peer review process (Phase 4).

3. Results
After combining all searches (academic and guideline databases, and website searches
of professional associations), 3778 reports were identified. Then, 177 duplicates were
removed, and 3132 were excluded after title and abstract screening. Finally, 469 full text
reports were retrieved, of which 35 were related to cataract. Of the 35 reports, 26 were
excluded after full text screening, and nine CPGs went through to the appraisal stage,
five of which were excluded (Figure 1; Table 3). This left four CPGs eligible for inclusion.
The median AGREE II score for the four selected CPGs was 49.4 (range 45–53.5), while
the median score of the five excluded CPGs was 17.2 (range 12–29.5). The results of the
screening process and exclusion reasons are summarized in Figure 1.

Table 3. AGREE II scores for the Clinical Practice Guidelines (CPGs) that were selected for appraisal
after full text screening.

Average AGREE II Scores

Clinical Practice Guideline (CPG) Item Number(s)
4 7 8 12 22 4, 7, 8, 10, 12, 13, 15, 22, 23
CPGs selected for inclusion after appraisal
National Institute for Health and Care Excellence (NICE), 2017, Cataracts
7 7 7 7 7 53.5
in adults; management [14]
American Academy of Ophthalmology, 2016, Cataract in the Adult Eye
5 6.5 4 6 7 49.5
Preferred Practice Pattern [15]
Rajavi et al., 2015, Customized clinical practice guidelines for
5 3 4 6.5 6.5 49.5
management of adult cataract in Iran [16]
The Royal College of Ophthalmologists and Clinical Council for Eye
Health Commissioning, 2018, Commissioning guide: Adult cataract 7 7 6 5 4.5 45
surgery [17]
CPGs excluded after appraisal
The Royal College of Ophthalmologists and the Royal College of
6.5 3 5 3.5 1 29.5
Anaesthetists, 2012, Local Anaesthesia for Ophthalmic Surgery
The Royal College of Ophthalmologists, 2018, Ophthalmic Services
2 1 1 1 1 15.5
Guidance: Theatre Procedures
Vision 2022, 6, 36 5 of 23

Table 3. Cont.

Average AGREE II Scores

Clinical Practice Guideline (CPG) Item Number(s)
4 7 8 12 22 4, 7, 8, 10, 12, 13, 15, 22, 23
The Royal College of Ophthalmologists, 2016, Ophthalmic Services
2.5 1 1 1 1 14.5
Guidance: Managing an outbreak of postoperative endophthalmitis
The Royal College of Ophthalmologists, 2018, Ophthalmic Services
2 1 1 1 1 14.5
Guidance: Theatre facilities and equipment
The Royal College of Ophthalmologists and the UK Ophthalmology
Vision 2022, 6, x FOR PEER REVIEW 5 of 20
Alliance, 2018, Quality Standard: Correct IOL implantation in 1 1 1 1 1 12
cataract surgery

Figure 1. Flow chart of the screening process.

TableThe following
3. AGREE fourfor
II scores CPGs were included:
the Clinical Practice Guidelines (CPGs) that were selected for appraisal
1. National
after full Institute for Health and Care Excellence (NICE), 2017, Cataracts in adults;
text screening.
management [14].
2. Average AGREE2016,
American Academy of Ophthalmology, II Scores
Cataract in the Adult Eye Preferred
Clinical Practice Guideline (CPG)Practice Pattern [15]. Item Number(s)
3. 4
Rajavi et al., 2015, Customized 7clinical8 practice
12 guidelines
22 4,for
7, 8, 10, 12, 13, 15,of22,
management 23
adult
CPGs selected for inclusion after appraisal
cataract in Iran [16].
National Institute for Health and Care Excellence (NICE),
7 7 7 7 7 53.5
2017, Cataracts in adults; management [14]
American Academy of Ophthalmology, 2016, Cataract in
5 6.5 4 6 7 49.5
the Adult Eye Preferred Practice Pattern [15]
Vision 2022, 6, 36 6 of 23

4. The Royal College of Ophthalmologists and Clinical Council for Eye Health Commis-
sioning, 2018, Commissioning guide: Adult cataract surgery [17].
CPGs 1 and 4 were published by organizations based in the United Kingdom, CPG 2 is
from the United States, and CPG 3 is from Iran. CPGs 1 and 2 drew evidence directly from
original research (such as systematic reviews, RCTs, and observational studies), whereas
CPG 3 drew evidence from other CPGs (namely the American Academy of Ophthalmol-
ogy’s 2006 and 2011 CPGs, Canadian Ophthalmological Society’s 2008 CPG, and the Royal
College of Ophthalmologists’ 2010 CPG). CPG 4 drew evidence from a mixture of original
research and other organizations’ CPGs (such as NICE guidelines).
Only CPGs 1–3 reported the quality of evidence supporting their recommendations
(Table 4). CPGs 1 and 2 used GRADE to report quality ratings [18]: In CPG 1, 28% of rec-
ommendations were supported by high-quality evidence, whilst 50% of recommendations
were supported by low-quality evidence; in contrast, CPG 2 judged that 86% of recommen-
dations were supported by good quality evidence and only 3% of the recommendations
were supported by insufficient evidence. CPG 3 used its own method of reporting quality
(Table 4 legend) and found that 38% of the recommendations were supported by evidence
at the level of a randomized clinical trial, systematic review or meta-analysis.

Table 4. Quality of evidence and strength of recommendation of the included Clinical Practice
Guidelines (CPGs).

Strength of Recommendation,
Quality of Evidence, n (%) *
Clinical Practice Guideline n (%)
High/Good Moderate Low/Insufficient Strong Discretionary
CPG 1: National Institute for Health and Care
Excellence (NICE), 2017, Cataracts in adults; 6 (27) 5 (23) 11 (50) 36 (75) 12 (25)
management [14] **
CPG 2: American Academy of
Ophthalmology, 2016, Cataract in the Adult 64 (86) 8 (11) 2 (3) 72 (97) 2 (3)
Eye Preferred Practice Pattern [15].
CPG 3: Rajavi et al., 2015, Customized clinical
practice guidelines for management of adult I: 31 (38) II: 11 (14) III–IV: 39 (48) - -
cataract in Iran [16] ***
CPG 4: The Royal College of
Ophthalmologists and Clinical Council for
Eye Health Commissioning, 2018, - - - - -
Commissioning guide: Adult cataract
surgery [17] ***
* Definitions of quality: CPGs 1 and 2: high/good, moderate and low/insufficient quality ratings defined by
GRADE [18]. CPG 3: I Randomized clinical trials; Systematic reviews; Meta-analysis. II Controlled clinical study
without randomization at least one; Well-designed cohort study; Well-designed case–control; Cross sectional
study. III Surveys; descriptive; case series studies. IV Experts opinion; consensus. ** Quality of evidence is based
on 22 groups of recommendations, and strength of recommendation is based on 48 recommendations (some
groups contain multiple recommendations). *** Strength of recommendations or quality of evidence not reported
in the CPG.

Only CPGs 1 and 2 reported the strength of recommendation (Table 4). For CPG 1,
three quarters of the recommendations were strong, and the other one quarter of their
recommendations were discretionary (where the trade-offs between benefits and risks were
less certain). For CPG 2, 97% of the recommendations were strong, with only 3% reported
as discretionary.
A summary of the eye care intervention recommendations from the four CPGs are
presented in Appendix A Table A1. After grouping the recommendations, 65 recommenda-
tions related to pre-operative interventions, 55 recommendations related to intra-operative
interventions, and 30 related to post-operative interventions.
Vision 2022, 6, 36 7 of 23

Most of the strongly recommended interventions had good quality evidence sup-
porting them, for example, weighing up risks and benefits of surgery with the patient,
use of appropriate biometry, small incision surgery, prepping with povidone-iodine, and
appropriate counselling of the patient regarding complications and post-operative care.
A minority of interventions were strongly recommended without high quality ev-
idence. For example, no evidence was identified for the recommendation to offer eye
protection for patients whose eye shows residual effects of anesthesia at time of discharge
after surgery.
There are instances where the CPGs make recommendations that do not align. For
example, CPGs 1 and 4 indicate that immediate sequential bilateral cataract surgery (ISBCS)
(i.e., bilateral cataract surgery performed in the same session) can be considered in low-
risk patients; whereas CPG 3 recommends that surgery should be performed in separate
sessions in patients with bilateral cataract.

4. Discussion
Our systematic review found four CPGs relating to cataract that met our inclusion
criteria. In the three CPGs where quality of evidence was evaluated, high-quality evidence
was available for 18% (CPG 2), 86% (CPG 1) and 38% (CPG 3) of the interventions rec-
ommended. In the two CPGs where strength of recommendation was presented (CPGs
1 and 2), 75% and 97% of interventions were strong recommendations, respectively. The
recommendations were broad in scope, covering pre-operative (43%), intra-operative (37%),
and post-operative interventions (20%).
A minority of interventions were strongly recommended without high quality ev-
idence. However, in some cases, conducting a study might be unethical or impractical.
For example, it would be unethical to randomize patients to a study arm where they are
not offered eye protection, as this could lead to complications such as corneal abrasions.
Since eye protection (e.g., plastic eye shields) is inexpensive, has minimal risk of causing
harm and could avert complications, it seems reasonable to make a strong recommendation
for eye protection despite the lack of evidence. Additionally, it would be unethical to
perform a trial comparing cataract surgery versus no cataract surgery (as this would leave
some participants visually impaired). Therefore, while there are research and trial data
comparing different cataract procedures, there is no evidence from randomized controlled
trials for cataract surgery per se.
The four included CPGs were published between 2015 and 2018. However, CPG 3
itself sourced its recommendations from four other CPGs that were published between 2006
and 2011 [16]: the American Academy of Ophthalmology’s 2006 and 2011 CPGs [15,19], the
Canadian Ophthalmological Society’s 2008 CPG [20], and the Royal College of Ophthalmol-
ogists’ 2010 CPG [21]. The Royal College of Ophthalmologists’ 2010 CPG is now ‘archived’
and no longer in use. The American Academy of Ophthalmology’s 2006 and 2011 CPGs
have now been replaced by the updated 2016 version, which is included in this systematic
review (CPG 2). Thus, the recommendations outlined in CPG 3 are based on older CPGs,
so CPG 3 may contain recommendations that are no longer in current best practice. For
example, CPG 3 indicates that intracameral antibiotics are not recommended, which is not
in line with recommendations from CPGs 1 and 2 that support the use of an intracameral
antibiotic, cefuroxime.
There was a consistent view across the CPGs that, pre-operatively, patients should
be given adequate information to help them weigh up the risks and benefits of cataract
surgery, and the patient’s individual preferences and needs should be considered. Use of
biometry and keratometry prior to cataract surgery was emphasized by three of the four
CPGs. Intraoperatively, there was a consistent view that the preferable method for cataract
surgery is small incision surgery under local anesthesia, and the patient’s eyes should be
prepped with povidone-iodine. Post-operatively, it was recommended that patients are
given adequate information regarding their post-operative care, and topical steroids or non-
steroidal anti-inflammatory drugs should be offered to reduce post-operative inflammation,
Vision 2022, 6, 36 8 of 23

particularly in patients at risk of cystoid macular oedema. Two CPGs also recommended
that providers of cataract services should be able to provide commissioners with data to
monitor quality, outcomes, and adverse events. Finally, counselling patients regarding the
risk factors for developing cataracts, such as smoking, sun exposure, and long-term steroid
use, was recommended by two CPGs.
There are other instances where the CPGs make recommendations that are somewhat
conflicting. For example, there are conflicting recommendations regarding ISBCS. Whilst
there is evidence supporting ISBCS [22,23], surgeon willingness to perform ISBCS varies,
which may be due to regional differences in surgical practice. For example, ophthalmol-
ogists in the UK cite the lack of Royal College and medico-legal approval for ISBCS as a
barrier to performing ISBCS [24]. In addition, attitude to, and acceptance of, ISBCS has
changed over time [25], and earlier CPGs may have been more reluctant to recommend
ISBCS compared to more recent CPGs due to lower acceptance of ISBCS at the time. Ongo-
ing systematic reviews and accumulation of evidence over time are likely to resolve this
uncertainty [26].
Very few CPGs met the inclusion criteria, which is a surprising finding given that
cataract is such a common condition, and in many settings, cataract surgery is one of the
most frequently performed operations [27]. Four CPGs were excluded due to unmanaged
conflicts of interest. We recommend that in future, organizations preparing CPGs develop
a clear and transparent approach to the management of conflicts of interest. We would also
recommend that future CPGs draw on the Appraisal of Guidelines for Research and Evaluation
II (AGREE II) tool [12], to ensure the quality and structure of their CPG before distributing
it for wider use.
A limitation of our methodology is that we restricted our search to English language
papers only, and thus may have missed CPGs that are published in non-English speaking
settings. This decision was due to feasibility considerations, including the labour-intensive
nature of screening and translation of CPGs in all official WHO languages. Another
limitation is that some CPGs were excluded based on an absence of information regarding
author affiliation, as lack of author affiliation does not necessarily mean that a conflict of
interest is present. Additionally, the publication year of the CPG may not reliably reflect
how up-to-date the cited evidence was. For instance, CPG 3 drew on evidence from other
published CPGs, half of which were published prior to 2010. Given that cataract surgery is
a long-standing, well-established and cost-effective intervention, this may limit the amount
of new evidence in this field. As only four CPGs were identified, and only one was from a
low/middle-income country (LMIC), the recommendations drawn from these four CPGs
may only be applicable in certain settings.
Due to timeline constraints for the development of the PECI, the literature search was
conducted in April 2020, so CPGs published subsequently were not included in this study.
We may have missed more recent guidelines that can be considered in future updates to
the PECI, such as “Cataract—Treatment of Adults, Ministry of Health British Columbia,
2021” [28], and “Cataract in the Adult Eye Preferred Practice Pattern, American Academy
of Ophthalmology, 2021” [29]. Additionally, the global COVID-19 pandemic, which was
declared by the WHO in 2020 [30], had a major impact on clinical practice. For example,
some updated guidelines, such as “Management of Cataract in India Revised in August
2020, VISION 2020: The Right to Sight—INDIA” [31], recommended organizational changes
in operating theatres. These guidelines should be considered in future PECI updates.
Among the cataract CPGs from LMIC settings, only one CPG from Iran met the
inclusion criteria for our review. Cataract recommendations in LMIC settings may differ
from those in high-income settings; for example, resource constraints in some countries
may mean that recommendations cover how to prioritize patients for cataract surgery
according to level of need. To address this, a broad range of public health, academic and
clinical professionals from all WHO regions, with a particular focus on LMIC settings,
were involved in all stages of development of the PECI. There is a pressing need for more
Vision 2022, 6, 36 9 of 23

high-quality CPGs from LMIC settings, particularly as cataract is highly prevalent in

these regions.

5. Conclusions
The results presented in this paper will assist in informing Phases 3 and 4 of the PECI
development process, with the ultimate goal of developing a package of evidence-based
eye care interventions for cataract [2].

Supplementary Materials: The following are available online at https://www.mdpi.com/article/10

.3390/vision6020036/s1, Supplementary Material S1: PRISMA reporting guidelines; Supplementary
Material S2: Search strategy for academic databases; Supplementary Material S3: Guideline databases
and the websites of professional ophthalmology and optometry associations searched.
Author Contributions: Conceptualization, J.R.E. and S.K.; methodology, J.R.E. and S.K.; software,
I.G.; validation, J.H.Z., J.R., C.N.L., S.S. and G.L.; formal analysis, J.H.Z. and J.R.; investigation,
J.H.Z., J.R. and C.N.L.; resources, not applicable; data curation, J.H.Z., J.R. and C.N.L.; writing—
original draft preparation, J.H.Z.; writing—review and editing, J.H.Z., J.R., C.N.L., I.G., S.S., G.L.,
J.R.E. and S.K.; visualization, J.H.Z.; supervision, J.R., J.R.E. and S.K.; project administration, J.H.Z.;
funding acquisition, not applicable. All authors have read and agreed to the published version of the
manuscript.
Funding: J.R.’s appointment at the University of Auckland is funded by the Buchanan Charitable
Foundation, New Zealand.
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: Data generated from this review will be available upon reasonable
request from Justine Zhang (justine.zhang@lshtm.ac.uk).
Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design
of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or
in the decision to publish the results.
Disclaimer: The views expressed in this paper are those of the authors and do not necessarily reflect
the views of WHO.

Appendix A

Table A1. Summary of the recommended interventions for cataract, identified from Clinical Practice
Guidelines (CPGs) that met the inclusion criteria. The corresponding CPGs, highest level of quality
of evidence, and the strength of recommendation are presented.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
Pre-operative interventions
Cataract surgery is indicated in patients with
cataracts causing vision loss, phacomorphic
glaucoma, lens-induced uveitis, or posterior 3 IV -
segment diseases where the cataract is
limiting the retinal examination/treatment.
Patients should be given oral and written 1 Moderate Strong
information about cataract surgery, in an
accessible format. 4 - -
Weigh up the indications, risks, and benefits 1 High Strong
of cataract surgery with the patient. 3 I -
Vision 2022, 6, 36 10 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
In patients with cataract in only one eye,
surgery is recommended if the advantages 3 III -
outweigh the risks.
Do not restrict access to cataract surgery 1 High Strong
based on visual acuity; it should be based on
individual need. 4 - -
For patients who require a certain visual
acuity for their occupation, cataract surgery is
3 IV -
indicated even when the patient does not
experience functional deficits.
Offer second eye cataract surgery using the
1 Moderate to high Strong
same criteria as for first eye surgery.
In some cases of anisometropia, earlier
surgical intervention for the second eye is
recommended, but the time between surgeries 3 IV -
should be long enough to first eye surgical
complications.
In patients with bilateral cataract, it is
recommended that surgery is performed in
3 I -
separate sessions to achieve better
binocular vision.
In patients with bilateral cataract, it is
recommended that surgery is performed in
separate sessions due to the risk of 3 III -
endophthalmitis and toxic anterior
segment syndrome.
Immediate sequential bilateral cataract
surgery should be considered for people who 1 Low to moderate Discretionary
are at low risk of operative and post-operative
complications, and for people who require
general anaesthesia. Potential benefits and
risks should be fully discussed with patients 4 - -
pre-operatively.
Cataract surgery may reduce intraocular
pressure in patients with angle 3 II -
closure glaucoma
Simultaneous cataract and glaucoma surgery
is recommended if there is a risk of blindness
3 IV -
due to increased intraocular pressure
post-operatively.
Use biometry (preferably optical biometry 1 Low Strong
over ultrasound biometry) and keratometry to
2 III, good quality Strong
estimate axial length and central corneal
curvature, respectively. 3 I -
Repeat A-scan biometry if: the axial length is
>26 mm or <21 mm; keratometry is >47 D or
<41 D; astigmatism is >2.5 D; axial length
3 III -
difference between the two eyes is >0.7;
keratometry difference between the two eyes
is >0.9.
Vision 2022, 6, 36 11 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
Consider corneal topography for people with
irregular astigmatism or previous 1 Low Discretionary
refractive surgery
For patients with previous refractive surgery,
use adjusted formulas to calculate the 1 Very low to moderate Strong
intraocular lens power. Advise them that
refractive outcomes after cataract surgery are 3 IV -
difficult to predict.
Documentation should be kept by the
treatment centre for all patients undergoing 3 II -
refractive surgery.
Surgeons should consider optimizing a
1 low Strong
manufacturer’s recommended intraocular
lens constant, e.g., based on their previous
3 IV -
refractive outcomes.
Consider using the first-eye refractive
outcome to guide calculations for the
1 Very low to low Discretionary
intraocular lens power for second-eye
cataract surgery.
In eyes with abnormal size, use Holladay 2 or
3 IV -
Haigis formulas.
Use new generation formulas to calculate the
3 III -
intraocular lens power.
Patients should be informed of the potential
inaccuracy of intraocular lens power
calculations and that further surgery may be 2 III, good quality Strong
required to achieve the target
refractive outcome.
Consider using a validated risk stratification
algorithm to identify people at increased risk 1 Low Discretionary
of complications during and after surgery.
Explain the results of risk stratification to the
patient and discuss how it may affect 1 Low Strong
decision-making.
In cases where the cataract surgery is likely to
be complex, and there may be a high risk of
complications, or the surgeon is not
experienced enough, the surgery should be 3 II -
performed by a more experienced surgeon or
the patient should be referred to a facility
with more expertise.
If a retinal detachment is found on
pre-assessment, consider combined 3 III -
vitrectomy and cataract surgery.
In patients with Fuchs’ dystrophy and
cataract, combined cataract and corneal 3 IV -
transplant can be considered.
Vision 2022, 6, 36 12 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
If possible, phacoemulsification should be
performed before penetrating keratoplasty if 2 III, good quality Strong
visualization is adequate.
Explain to people who are at risk of
1 Low Strong
developing dense cataracts that delayed
surgery can result in an increased risk of
2 III, good quality Strong
complications.
Do not offer multifocal intraocular lenses for
1 Very low to moderate Strong
patients with cataracts.
The suitability of multifocal intraocular lenses
for patients with amblyopia, or abnormalities
2 III, insufficient quality Discretionary
of the cornea, optic nerve or macula must be
carefully considered.
Offer monovision to patients with
1 Very low to moderate Strong
anisometropia, or pre-operative monovision.
Assess tear function, as tear dysfunction may
2 II+, good quality Strong
compromise the postoperative result.
2 II+, good quality Strong
Counsel patients to stop smoking.
3 I -
Recommend brimmed hats and ultraviolet-B 2 II-, good quality Strong
blocking sunglasses. 3 I -
Recommend safety eyeglasses in high-risk
2 III, good quality Strong
activities at work or recreation.
Advise patients that currently there is
insufficient evidence to support the use of 2 III, good quality Strong
pharmacological treatments for cataract.

Advise patients that long-term use of steroids 2 II+, moderate quality Strong
is associated with increased risk of cataract. 3 I -
Vitamin supplements do not reduce the
3 I -
progression of cataracts.
Increased risk of cataracts should be
3 II -
discussed with diabetic patients.
In patients with cataracts who do not want
surgery, the increased risk of accidents and 3 II -
bone fractures should be discussed.
Patients with cataracts should undergo
surgery as soon as possible, preferably with a
3 I -
waiting time of less than 2–3 months to avoid
possible falls, fractures and accidents.
In a functionally monocular patient, tell the
patient that blindness is one of the risks of 2 III, good quality Strong
cataract surgery.
Patients should be informed pre-operatively
regarding the possibility of visual impairment 2 III, good quality Strong
continuing after surgery.
Vision 2022, 6, 36 13 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
A medical pre-operative evaluation should be
performed by the surgeon, and where 2 III, good quality Strong
appropriate, the primary care physician, to
determine the appropriateness and timing 3 I -
of surgery.
Pre-operative laboratory testing is
2 I+, good quality Strong
not indicated.
Consider the patient’s preferences and needs 1 Moderate Strong
when selecting the post-operative
refractive target. 2 III, good quality Strong
α-1 antagonists should be discontinued before
surgery due to the high risk of floppy iris 3 II -
syndrome.
Anti-coagulant and anti-platelet medications
2 I-, good quality Strong
should generally be continued.
For patients on warfarin, the international
normalized ratio should be in the 2 I+, good quality Strong
therapeutic range.
Aspirin should only be discontinued
peri-operatively if the risk of bleeding 2 I-, good quality Strong
outweighs its potential benefit.
Discontinuation of anti-coagulant medications
is not recommended, except for warfarin and 3 I -
clopidogrel.
Documentation of which eye is being
operated on, IOL power, medications,
3 II -
previous diseases, etc, should be filled in
immediately before surgery.
All patients with cataracts should be informed
about the risk of posterior capsular 3 III -
opacification before undergoing surgery.
The risk of aggravation of diabetic retinopathy
should be discussed in patients with diabetes 3 III -
who are undergoing cataract surgery.
If possible, treatment of proliferative diabetic
retinopathy and macular oedema should be 3 IV -
carried out before cataract surgery.
Risk of retinal detachment should be
discussed with high-risk patients, e.g., young, 3 I -
male, high myope.
Patients with age-related macular
degeneration should only undergo cataract
surgery is there is a chance for improved
3 I -
vision, and the patient should be informed of
the risk of worsening of their macular
degeneration.
Vision 2022, 6, 36 14 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
Patients should be counselled prior to surgery
if they have a comorbidity that is associated
with intra-ocular complications or the 2 III, good quality Strong
potential for reduced improvement in
visual function.
In patients with uveitis, inflammation should
be at its best level of control, for ≥3 months
prior to elective surgery, and
anti-inflammatory medications should be 2 III, good quality Strong
started prior to surgery. The medical regimen
should be individualized, based on the
severity of previous episodes of uveitis.
In patients with uveitis, surgical planning
should take into account the possible need for
2 III, good quality Strong
further procedures secondary to uveitis
complications, e.g., secondary glaucoma.
Ensure that the correct medical notes are used
by confirming the patient’s name, address and
date of birth, and ensure that biometry results
1 Moderate Strong
are securely attached to the patient’s notes.
Record the patient’s choice of refractive
outcome in the medical notes.
Staff in the cataract pathway should be able to
provide evidence of competencies and 4 - -
continuing professional development.
While certain diagnostic procedures may be
delegated to appropriately trained staff
supervised by the ophthalmologist, 2 III, good quality Strong
interpretation of these procedures requires the
clinical judgement of the ophthalmologist.
Intra-operative interventions
The predominant method of cataract surgery
2 I+, good quality Strong
in high income countries is small incision
phacoemulsification with foldable intraocular
3 I -
lens implantation.
Small incision surgery is generally preferred. 2 I-, good quality Strong
Only an ophthalmologist has the medical and
microsurgical training as part of a
2 III, good quality Strong
comprehensive resident experience needed to
perform cataract surgery.
Ensure that surgeons in training are
1 Low Strong
well supervised.
Local anaesthesia is preferred, but in some
2 I++, good quality Strong
cases general anaesthesia is indicated.
Offer sub-Tenon’s or topical anaesthesia. 1 Very low to high Strong
Consider hyaluronidase as an adjunct to
1 Low Discretionary
sub-Tenon’s anaesthesia
Vision 2022, 6, 36 15 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
If both sub-Tenon’s and topical are
contraindicated, consider peribulbar 1 Very low to high Discretionary
anaesthesia.
Do no offer retrobulbar anaesthesia. 1 Very low to high Strong
Consider sedation as an adjunct to
anaesthesia for people who are anxious, have
1 Low Discretionary
postural problems, or where surgery is
expected to take longer than usual.
There is insufficient evidence to recommend
2 I+, good quality Strong
sedation over local anaesthesia.
When sedation is used, intravenous access is
2 I+, good quality Strong
recommended.
The choice of local anaesthesia is based on 2 I+, good quality Strong
patient and surgeon preference. 3 I -
Monitoring during administration of
anaesthesia generally includes a heart
monitor, pulse oximetry, blood pressure and 2 III, good quality Strong
respiratory rate, performed by a qualified
staff member.
Before giving anaesthesia, use a WHO
surgical safety checklist to check the patient’s
identity, consent form, printed biometry
results, medical notes, preferred refractive 1 Moderate Strong
outcome, lens, marked eye to be operated on,
and consistency of lens formulas and
calculations.
Ensure there is only one matching intraocular
lens in the theatre, and that alternative 1 Moderate Strong
intraocular lenses (e.g., noncapsular-bag
lenses) are in stock in the event of surgical 2 III, good quality Strong
complications.
As non-capsular bag fixation may increase the
potential for optic tilt/decentration, the
surgeon should consider whether multifocal
2 III, insufficient quality Discretionary
intraocular lenses or lenses with higher
degrees of negative spherical aberration
should be used.
A peripheral iridectomy should be performed
to prevent the risk of pupillary block
2 III, good quality Strong
associated with an anterior chamber
intraocular lens.
Consider on-axis surgery or limbal-relaxing
1 Moderate Discretionary
incisions to reduce astigmatism.
Only use femtosecond laser-assisted cataract
1 Low Strong
surgery as part of a randomized control trial.
There are certain types of cataracts, e.g.,
posterior polar, for which the femtosecond 2 II-, moderate quality Strong
laser should not be used.
Vision 2022, 6, 36 16 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
In patients at risk of floppy iris syndrome,
consider intracameral phenylephrine to 1 Low Discretionary
increase pupil size.
Follow a protocol for posterior capsule
rupture that covers vitreous removal from the
No evidence was
anterior chamber, minimizing retinal traction, 1 Strong
identified
lens fragment and soft lens matter removal,
and implications of intraocular lens insertion.
Do not use capsular tension rings in routine
1 High Strong
cataract surgery.
Consider use of capsular tension rings in
1 High Discretionary
patients with pseudoexfoliation.
Use pre-operative anti-septics, and
1 Very low to high Strong
commercially or pharmacy prepared
intracameral cefuroxime, to prevent
2 I-, good quality Strong
endophthalmitis.
Intracameral antibiotic injections are not
recommended due to the toxic effects and
3 III -
likelihood of reduction in corneal
endothelial cells.
Discourage use of antibiotic in the
2 III, moderate quality Strong
irrigation bottle.
Construct and close incisions so that they are
2 II-, moderate quality Strong
watertight, to reduce risk of infection.
Eyelashes should be prepped with 10%
3 II -
povidone-iodine.
The conjunctiva should be prepped with 5% 2 II-, moderate quality Strong
povidone-iodine. 3 II -
In immediate sequential bilateral cataract
surgery, the second eye should be treated as
the eye of a different patient would be treated,
2 III, good quality Strong
using separate prepping, draping,
instrumentation, irrigation solutions, and
medications.
In patients with planned immediate
sequential bilateral cataract surgery, if a
complication occurs during first eye surgery, 2 III, good quality Strong
then second eye surgery should be
reconsidered and carried out at a later date.
The surgeon should avoid working close to
2 III, good quality Strong
the cornea.
The surgeon should ensure proper orientation
2 III, good quality Strong
of the intraocular lens.
If there is vitreous loss, the surgeon should
perform an anterior vitrectomy and implant
2 III, good quality Strong
an intraocular lens with appropriate size
and design.
Vision 2022, 6, 36 17 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
In patients with uveitis, excessive iris
manipulation should be minimized and
post-operative short-acting topical mydriatic
2 III, good quality Strong
agents may help prevent synechiae formation.
Adjunctive steroids at the time of surgery
should be considered.
Use intraocular lenses with sharp angles to
3 I -
reduce the risk of posterior capsule opacity.
Use of aspheric intraocular lenses is
recommended to achieve better contrast
sensitivity and visual performance; but in
conditions such as zonular rupture, 3 I -
astigmatism, or after hyperopic corneal
refractive surgery, spherical intraocular lenses
should be implanted.
In the process of using multifocal intraocular
lenses, careful patient selection, consultation,
3 IV -
and utilization of preoperative examinations
are vital.
Base the use of multifocal/adjustable lenses
on patient needs and desires, and after giving
3 I -
the patient information about the advantages
and disadvantages.
To use toric intraocular lenses in patients with
astigmatism, accurate preoperative
calculations, correct marking of the steep axis, 3 IV -
and implanting the intraocular lenses in
correct axis should be considered.
Visual outcomes after implantation of UV
filter intraocular lenses and blue filter 3 I -
intraocular lenses are comparable.
When the posterior chamber intraocular
lenses is placed in the ciliary sulcus,
3 IV -
decreasing the power by 0 to 1.5 dioptres
should be considered.
Staining of the anterior capsule is
recommended in mature cataracts, 3 I -
complicated cataracts and paediatric cataracts.
A smaller capsulorhexis (4.5–5 mm) is
preferable to a larger one since it decreases the 3 I -
chance of posterior capsule opacification.
It is recommended that hydrodissection and
hydrodelineation be performed to reduce
tension on the zonules, facilitate cortex 3 I -
removal, and reduce the chance of posterior
capsule opacification.
Floppy iris syndrome can be anticipated in
patients using oral α-1 antagonists, and 2 II-, moderate quality Strong
pharmacologic approaches, viscomydriasis,
and pupil-expansion devices should be used 3 I -
to manage floppy iris syndrome.
Vision 2022, 6, 36 18 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
A small pupil should be enlarged, e.g., with
3 IV -
hooks/rings.
Performing phacoemulsification with a
torsional probe is preferable to longitudinal
3 I -
probes since there is a smaller risk of
corneal trauma.
In patients with zonular weakness, applying
3 I -
capsular tension rings is recommended.
It is recommended to implant intraocular
3 III -
lenses using injectors.
In the absence of inadequate capsular bag
support, the surgeon should determine a
suitable intraocular lens to be implanted into
3 III -
the ciliary sulcus. Implantation of multifocal
and aspheric intraocular lenses in the ciliary
sulcus are not recommended.
In cases of posterior capsular rupture and
inadequate capsular support for in-the-bag
intraocular lens implantation, anterior
3 III -
chamber intraocular lenses, scleral fixation
posterior chamber intraocular lenses, or iris
fixation intraocular lenses may be used.
Subconjunctival antibiotic injection may be
recommended to reduce the chance of 3 III -
postoperative endophthalmitis.
Post-operative interventions
The operating ophthalmologist should
provide aspects of post-operative care that are
within their competence, and should inform
patients about the symptoms of possible
2 III, good quality Strong
complications and details regarding their
post-operative care. This includes instructions
to notify the ophthalmologist promptly if
problems occur.
At the first review appointment after cataract
surgery, give patients information about eye
drops, what to do if their vision changes, who
1 Low Strong
to contact for queries, when to buy new
spectacles, second eye cataract surgery, how
to manage ocular comorbidities.
It is recommended to perform the first
post-operative examination up to 24 h after
the surgery. The exact timing of other
3 IV -
postoperative visits depends on surgical
complications, and surgeon and
patient preference.
In high risk conditions such as monocular
patients, glaucomatous eyes and surgical
complications, the first post-operative visit 3 IV -
should be performed within 24 h and more
frequent follow-up examinations are needed.
Vision 2022, 6, 36 19 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
Patients should always have access to an
2 III, good quality Strong
ophthalmologist.
A final refractive visit should be made to
2 III, good quality Strong
provide a prescription for spectacles.
Final evaluation of refractive power should be
performed 2 weeks post-operatively in
patients with small corneal incisions (under
3 IV -
3.5 mm) and 6 weeks post-operatively in
patients with larger incisions or
extracapsular surgery.
If a surgeon encounters a higher incidence of
endophthalmitis compared to what is
reported in the literature, the source of this
3 IV -
should be investigated by taking microbial
cultures from the personnel, surgery room
and devices.
Patient education brochures should be given
3 II -
to patients after surgery.
Providers of cataract care should be able to
provide commissioners with outcome data, 1 Low Strong
and outcome data from primary care should
be fed back to the surgical team. Providers
and surgeons should use audit tools to
monitor quality, outcomes and adverse events 4 - -
in real time.
The surgical facility should comply with local
2 III, good quality Strong
and state regulations and standards.
Costlier new infection control measures that
do not have evidence-based support should
2 III, good quality Strong
not be arbitrarily imposed by
regulatory agencies.
If a wrong lens is implanted, refer to NHS
England’s Never Events policy, undertake a
root-cause analysis, and establish strategies 1 Moderate Strong
and implementation tools to prevent future
occurrences.
Offer topical steroids or non-steroidal 1 Very low to low Strong
anti-inflammatory drugs after cataract surgery
in patients at risk of cystoid macular oedema. 3 I -
Consider topical steroids in combination with
non-steroidal anti-inflammatory drugs after
1 Very low to low Discretionary
cataract surgery in patients at risk of cystoid
macular oedema.
Intraocular pressure should be monitored in
patients treated with post-operative 2 II-, good quality Strong
corticosteroids.
Vision 2022, 6, 36 20 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
In high-risk patients, e.g., pre-existing
glaucoma, the intraocular pressure should be
monitored in the early post-operative period 2 III, good quality Strong
and appropriate pressure-lowering
agents given.
There is no evidence that visual outcome is
improved by routine use of prophylactic
2 II+, moderate quality Strong
non-steroidal anti-inflammatory drugs at
≥3 months after cataract surgery.
Offer eye protection for patients whose eye
No evidence was
shows residual effects of anaesthesia at time 1 Strong
identified
of discharge after surgery.
Consider collecting visual function and
quality of life data for entry into an 1 Low Discretionary
electronic dataset.
Do not offer face-to-face first-day review to
patients who had uncomplicated 1 Low Strong
cataract surgery.
If endophthalmitis is suspected, refer to a
retina specialist to review the patient within
24 h. If review within 24 h is not possible, 2 I-, good quality Strong
perform an intravitreal tap and inject
of antibiotics.
When unacceptable refractive error results
after lens implantation, the risks of further
2 III, good quality Strong
surgery must be weighed against use of
spectacles or contact lens correction.
Patients with uveitis generally require greater
frequency and duration of topical
2 III, good quality Strong
anti-inflammatory treatment and should be
monitored closely.
YAG laser capsulotomy is indicated for
posterior capsular opacification where there is
a functional impact. The eye should be 2 III, good quality Strong
inflammation-free and the IOL stable prior to
performing a YAG capsulotomy.
High frequency post-operative antibiotics are
3 III -
recommended.
Topical steroids or non-steroidal
anti-inflammatory drugs to reduce 3 IV -
post-operative inflammation is recommended.
Ophthalmologists should be aware of
resistance to several antibiotics such as
penicillin and fluoroquinolones for treatment 3 III -
of postoperative staphylococcal
endophthalmitis.
Ophthalmologists should be aware of toxic
anterior segment syndrome and its 3 III -
predisposing factors.
Vision 2022, 6, 36 21 of 23

Table A1. Cont.

Strength of
Description of Intervention Relevant CPG(s) * Quality of Evidence ** Recommendation (Strong,
Discretionary) ***
To evaluate patient satisfaction, standard
questionnaires such as the VF14 will provide
3 IV -
greater insight into patient satisfaction than
visual acuity assessment.
* Clinical Practice Guidelines: CPG 1: National Institute for Health and Care Excellence (NICE), 2017, Cataracts
in adults; management [14]. CPG 2: American Academy of Ophthalmology, 2016, Cataract in the Adult Eye
Preferred Practice Pattern [15]. CPG 3: Rajavi et al., 2015, Customized clinical practice guidelines for management
of adult cataract in Iran [16]. CPG 4: The Royal College of Ophthalmologists and Clinical Council for Eye Health
Commissioning, 2018, Commissioning guide: Adult cataract surgery [17]. ** Definitions of quality for each
CPG: CPG 1: “GRADE was used to assess the quality of evidence for the selected outcomes as specified in ‘The
guidelines manual (2014)’ [32]. Where RCTs are available, these are initially rated as high quality and the quality
of the evidence for each outcome was downgraded or not from this initial point. If non-RCT evidence was
included for intervention-type systematic reviews, then these are initially rated as low-quality and the quality of
the evidence for each outcome was downgraded or not from this point”. CPG 2: “To rate individual studies, a
scale based on SIGN [33] is used. The definitions and levels of evidence to rate individual studies are as follows:
I++ High-quality meta-analyses, systematic reviews of randomized controlled trials (RCTs), or RCTs with a very
low risk of bias. I+ Well-conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias.
I- Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias. II++ High-quality systematic
reviews of case–control or cohort studies High-quality case–control or cohort studies with a very low risk of
confounding or bias and a high probability that the relationship is causal. II+ Well-conducted case–control or
cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal. II-
Case-control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship
is not causal. III Nonanalytic studies (e.g., case reports, case series). The body of evidence quality ratings are
defined by GRADE [18] as follows: Good quality: Further research is very unlikely to change our confidence in
the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence
in the estimate of effect and may change the estimate. Insufficient quality: Further research is very likely to have
an important impact on our confidence in the estimate of effect and is likely to change the estimate. Any estimate
of effect is very uncertain”. CPG 3: I Randomized clinical trials; Systematic reviews; Meta-analysis. II Controlled
clinical study without randomization at least one; Well-designed cohort study; Well-designed case–control; Cross
sectional study. III Surveys; descriptive; case series studies. IV Experts opinion; consensus. *** Definitions of
Strong and Discretionary: CPG 1: Strong recommendation: “We use ‘offer’ (and similar words such as ‘refer’
or ‘advise’) when we are confident that, for the vast majority of patients, an intervention will do more good
than harm, and be cost effective. We use similar forms of words (for example, ‘Do not offer . . . ’) when we are
confident that an intervention will not be of benefit for most patients’. Discretionary recommendation: ‘We use
‘consider’ when we are confident that an intervention will do more good than harm for most patients, and be
cost effective, but other options may be similarly cost effective. The choice of intervention, and whether or not to
have the intervention at all, is more likely to depend on the patient’s values and preferences than for a strong
recommendation, and so the healthcare professional should spend more time considering and discussing the
options with the patient”. CPG 2: Strong recommendation: “Used when the desirable effects of an intervention
clearly outweigh the undesirable effects or clearly do not”. Discretionary recommendation: “Used when the
trade-offs are less certain—either because of low-quality evidence or because evidence suggests that desirable and
undesirable effects are closely balanced”.

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eye care interventions. BMJ Open Ophthalmol. 2020, 5, e000533. [CrossRef] [PubMed]
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measuring quality-of-care in the context of Universal Health Coverage. PLoS ONE 2017, 12, e0172342. [CrossRef] [PubMed]
6. Keel, S.; Muller, A.; Block, S.; Bourne, R.; Burton, M.J.; Chatterji, S.; He, M.; Lansingh, V.C.; Mathenge, W.; Mariotti, S.; et al.
Keeping an eye on eye care: Monitoring progress towards effective coverage. Lancet Glob. Health 2021, 9, e1460–e1664. [CrossRef]
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