Psychiatric Quarterly (2022) 93:791–802

https://doi.org/10.1007/s11126-022-09996-1

ORIGINAL PAPER

Depressive Disorder Related Hospitalizations in Portugal

Between 2008–2015: a Nationwide Observational Study

Manuel Gonçalves‑Pinho1,2,3 · João Pedro Ribeiro3 · Lia Fernandes2,4,5 ·

Alberto Freitas1,2

Accepted: 11 June 2022 / Published online: 21 June 2022

© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022

Abstract
Depression is a prevalent disease, being one of the most relevant contributors of disabil-
ity in the overall global burden of diseases. Hospitalization episodes are important quality
indicators in psychiatric care. The primary aim of this study is to analyse depressive dis-
order related hospitalizations in Portuguese public hospitals and to detail clinical and soci-
odemographic differences among various subtypes of depression. Admissions with a pri-
mary diagnosis of depression in adult patients(> = 18 years) were selected from a national
mainland hospitalization database. ICD-9-CM codes were used to select the diagnoses of
interest: 296.2 × to 296.3x (Major depressive disorder), 300.4 (Dysthymic disorder) and
311 (Depressive disorder, not elsewhere classified). Birth date, sex, residence address, pri-
mary and secondary diagnoses, admission date, discharge date, length of stay (LoS), dis-
charge status, and hospital estimated charges were obtained. A total of 28,569 hospitaliza-
tions (22,387 patients) with a primary diagnosis of depression were analysed. In the 8-year
period of the study, 19.1% of all hospitalizations with a primary diagnosis of psychiatric
disorder were linked to Depression. Major Depressive episodes were the most common
(n = 15,384; 53.8%), followed by Depression unspecified episodes (n = 6,793; 23.8%),
and Dysthymia (n = 6,392; 22.4%). Most episodes occurred in female patients (70.2%;
n = 20,052), with a mean age of 50.6 years, and 37.0% (n = 10,564) of the episodes were
associated to other psychiatric comorbidities. Depressive disorders are one of the lead-
ing causes of hospitalization in Portuguese psychiatric departments, being responsible for
approximately 1 in 5 hospitalizations with a psychiatric diagnosis.

Keywords Depression · Major depressive disorder · Dysthymia · Hospitalization ·

Administrative data · Big data

Introduction

Depression is a prevalent disease, considered by WHO as one of the largest contributors

of disability and a major one to the overall global burden of diseases [1–3]. Depres-
sive symptoms may vary in severity and lead to different psychiatric disorders: major

* Manuel Gonçalves‑Pinho
manuelgpinho@med.up.pt
Extended author information available on the last page of the article

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792 Psychiatric Quarterly (2022) 93:791–802

depressive disorder (MDD) is one of the most severe forms of depression. Hospitali-
zations are common in patients with MDD and represent an important part of the eco-
nomic and clinical burden of the disease. Suicidal ideation and behaviour are one of the
leading causes of hospitalizations among patients with MDD, and about 12% of patients
with MDD are hospitalized throughout their lifetime [4, 5].
Hospitalizations arise as important indicators of MDD treatment. and are frequently
reserved for patients with severe clinical presentations of the disease, or as a last treat-
ment resource after outpatient care failure [4]. Previous studies reported that MDD hos-
pitalizations are costly and associated with high rates of readmissions, reinforcing the
importance of quality outpatient care and the upbringing of new treatments [4, 6].
The economic impact of depression in Portugal was estimated to a total annual cost
of PTE 246 billion (at 1992 prices), of which 80% corresponded to a loss of productivity
(temporary disability), 3% to suicide, and 17% attributable to direct healthcare costs [7].
The necessity of epidemiological studies regarding depression trends in Portugal has long
been recognized [8].
Point prevalence of depression in Portuguese psychiatric services was obtained in
three psychiatric censuses carried out in 1988, 1996, and 2001, which showed preva-
lences of 10.1%, 13.3%, and 4.9% respectively. The 1988 and 1996 censuses gathered
data referring only to psychiatric hospitals, while the 2001 census included all pub-
lic and private institutions. In the 2001 census, depression and its subclasses were the
most common diagnostic group (21.5%), followed by neuroses and schizophrenia (both
12.4%) and adjustment reactions (10.5%) [8].
Few longitudinal studies have analysed MDD related hospitalizations, none in Portu-
gal. The primary aim of this study was to analyse depressive disorder related hospitali-
zations in Portuguese public hospitals. The secondary aims of the study were to detail
clinical and sociodemographic differences among patients with major depressive disor-
der, dysthymia, and depression (unspecified).

Methods

Study Design and Reporting

A retrospective observational study was conducted using an administrative database

provided by the Authority for Health Services of the Portuguese Ministry of Health
(ACSS). Data analysis, reporting, and manuscript formatting follow the Reporting of
Studies Conducted using Observational Routinely-Collected Data (RECORD) statement
recommendations [9].

Data Source, Access, and Cleaning Methods

The database used in the study contains administrative anonymized data from all hos-
pitalizations registered in Portuguese mainland public hospitals. Data from private hos-
pitals and those located in the autonomous regions of the Azores and Madeira are not
included. Inpatient episodes (> = 24 h duration) from 2008 to 2015 were analysed.
The authors performed data cleaning by eliminating duplicate hospitalizations that
commonly occur in the district of Oporto in the North region of Portugal, where all
psychiatric patients must be pre-hospitalized in one central hospital (Hospital de

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Psychiatric Quarterly (2022) 93:791–802 793

Magalhães Lemos) before being transferred to their specific regional psychiatric hospi-
tal. All episodes registered in that hospital and from whose patients did not belong to its
coverage geographic area were excluded, this process was already used and described in
previous studies [10].
There were no data linkages between other databases than the one previously described.

Study Population and Setting

Hospitalization episodes from patients aged 18 or older with a primary diagnosis of depres-
sion and a discharge occurring between 2008–2015 were selected. International Classifica-
tion of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes were used to
select the diagnoses of interest. As previously reported, the most suitable case definitions
for detecting depression in administrative data vary depending on the specific context [11].
The primary diagnosis codes considered in this study were 296.2 × to 296.3x (Major
depressive disorder). Other diagnostic codes were also selected to obtain compari-
son groups between other depressive disorders: 300.4 (Dysthymic disorder) and 311
(Depressive disorder, not elsewhere classified), a group of diagnostic codes determined
to be less inclusive (higher specificity and lower sensitivity) [12]. Depressive episodes
associated with bipolar disorder were not included in the analysis as they were previ-
ously reported elsewhere [13].
All analysed hospitalization episodes occurred in Portuguese public hospitals. Portu-
gal has an estimated population of 10.3 M inhabitants, and most health services contact
episodes occur in the National Health Service (NHS) in primary and hospital care [14].

Variables

Hospitalization episodes were the unit of analysis. Individual characteristics and outcomes
were gathered from each hospitalization episode. Individual characteristics included soci-
odemographic variables: age at admission and sex; and administrative variables: type and
date of admission, primary and secondary diagnoses, medical/surgical procedures, and dis-
charge status.
The type of admission was dichotomized into elective or emergent admissions, while
the psychiatric comorbidities included: personality disorders (codes 301.x); substance
abuse (codes 303.x, 304.x and 305.x); intellectual disability (codes 317, 318 and 319)
and conduct disorders (codes 312.x).
Suicidal behaviour or self-inflicted injury was identified by the ICD-9-CM E codes
(external cause of injury codes) E950-E959 and diagnostic code V62.84. Diagnoses were
grouped in broader categories as defined by the Clinical Classification Software Classifi-
cation [15]. Outcomes analysed included length of stay (LoS) in days, in-hospital mortal-
ity, hospital estimated charges, and readmissions.
The Charlson Comorbidity Index (CCI) was used to assess and compare comorbidities
among hospitalization episodes. The authors used the enhanced ICD-9-CM coding algo-
rithm for Charlson Comorbidities proposed by Quan et al. [16].
We performed a subgroup analysis based on the type of depressive disorder, using as the
index group the MDD related hospitalizations.
Hospital charges were calculated from expenditure tables for the Portuguese National
Health Service hospital reimbursement as defined by governmental decree in 2009 (in
Diário da República) and were estimated using a diagnosis-related group-based budget

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allocation model. To compute readmissions, an anonymous patient identification approach

was conducted by cross-referencing three variables—sex, birth date, and place of resi-
dence. The average annual population from mainland Portugal was obtained from the Insti-
tuto Nacional de Estatística (INE—Statistics Portugal).

Statistical Methods

Descriptive statistical analyses, Independent Sample t-tests, and linear regression models
were performed using IBM SPSS Statistics v.25 for Windows (Armonk, NY: IBM Corp).

Results

In the 8 years of the study, there were 28,569 hospitalizations (associated with 22,387
patients) with a primary diagnosis of depression. Depression related hospitalizations
accounted for 19.1% of all hospitalizations with a primary diagnosis of a psychiatric dis-
order (episodes of > = 24 h and in patients aged 18 or older). Considering all hospitaliza-
tion episodes, 15,384 (53.8%) were due to Major Depressive episodes (single episodes:
n = 6,417; 22.5% and recurrent episodes: n = 8,967; 31.3%), 6,793 (23.8%) due to Depres-
sion, unspecified episodes (ICD-9-CM code 311) and 6,392 (22.4%) had Dysthymia (ICD-
9-CM code 300.4) as primary diagnosis (Table 1).
Portugal presents a mean hospitalization rate of 35.5 admissions per 100,000 inhabit-
ants (considering the mean annual number of hospitalizations and the adult resident popu-
lation of mainland Portugal) [17].
December was the month that registered a lower number of depression related hospitali-
zations (n = 2,022; 7.1%) – a trend seen in all the diagnostic groups considered in the study
–, whereas March was the month with the higher number of episodes (n = 2,572; 9.0%).
During the study period a linear and significant decrease (17.0%) on the total number
of hospitalizations occurred, with a maximum of 3,854 episodes in 2009 and a minimum
in 2015 (n = 3,200), (r = 0.942; B = -88.8; p < 0.001). From the three depression subgroups,
dysthymia related hospitalizations registered the most pronounced decrease during the
study period (r = 0.921; B = -68.9; p < 0.001), Major Depression episodes decreased but
without statistical significance (r = 0.644; B = -22.2; p = 0.085) and Depression unspecified
episodes (r = 0.058; B = 2.2; p = 0.891) remained stable.
Most episodes were associated with female patients (70.2%; n = 20,052), this trend was
registered in all diagnostic categories (79.1% Dysthymia; 68.4% Depression, unspecified,
and 67.3% Major Depressive Disorder).
The mean age of all patients analysed was 50.6 years (SD = 14.8). Depression, unspeci-
fied episodes were associated with the younger patients (mean age = 48.7; SD = 15.3), fol-
lowed by Dysthymia (mean age = 49.8; SD = 13.8) and Major Depressive Disorder (mean
age = 51.7; SD = 14.8); these differences are statistically significant (p < 0.001).
The median LoS for all episodes was 13.0 days, with Major Depressive disorder hospi-
talizations being the longest with a median LoS of 15.0 days. Most episodes were associ-
ated with a CCI of zero (87.7%) and the in-hospital mortality was 0.3%. During the study
period, 78.4% (n = 22,387) of the episodes were considered index hospitalizations, with an
8-year readmission rate of 1.28 hospitalizations per patient. The mean estimated hospitali-
zation charge was 2602.6€ per episode, leading to a sum of 74.4 M€ in the 8 years of the
study.

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 Table 1  Sociodemographic and clinical variables in patients hospitalized with a depressive episode in Portuguese public hospitals between 2008 and 2015
Major Depressive Disorder Dysthymia Depression, unspecified Total
Psychiatric Quarterly (2022) 93:791–802

(296.2x-296.3x) (300.4) (311)

n=; % 15,384; 53.8 6,392; 22.4 6,793; 23.8 28,569; 100

Sex 10,350; 67.3 5,058; 79.1 4,644; 68.4 20,052; 70.2
Female (n = ; %within disorder)
Age (mean; SD) 51.7; 14.8 49.8; 13.8 48.7; 15.3 50.6; 14.8
In-hospital mortality (n = ;%) 45; 0.3 5; 0.1 25; 0.4 75; 0.3
LoS (median days) 15.0; 9.0–24.0 12.0; 7.0–19.0 10.0; 4.0–17.0 13.0; 7.0–21.0
Charlson Comorbidity Index (CCI)
0 13,556;88.1 5,713;89.4 5,795;85.3 25,064; 87.7
1 1,341;8.7 516;8.1 728;10.7 2,585; 9.0
>2 487; 3.2 163; 2.6 270; 4.0 920; 3.2

SD Standard Deviation, LoS Length of Stay

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 796

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Table 2  Psychiatric comorbidities in patients hospitalized with a depressive episode in Portuguese public hospitals. Comorbidities were classified using the Clinical Classifi-
cation Software (CCS) approach
Major Depressive Disorder Dysthymia Depression, Total
(296.2x-296.3x) (300.4) unspecified (n = ; %)
(n = ; %within disorder) (n = ; %within disorder) (311)
(n = ; %within disorder)

Adjustment disorders 79; 0.5 61; 1.0 36; 0.5 1760.6

Anxiety disorders 965; 6.3 370; 5.8 587; 8.6 19226.7
Attention-deficit, conduct, and disruptive behavior disorders 69; 0.4 44; 0.7 122; 1.8 2350.8
Delirium, dementia, and amnestic and other cognitive disorders 381; 2.5 64; 1.0 159; 2.3 6042.1
Developmental disorders 344; 2.2 170; 2.7 198; 2.9 7122.5
Personality disorders 1506; 9.8 836; 13.1 824; 12.1 316611.1
Schizophrenia and other psychotic disorders 94; 0.6 22; 0.3 40; 0.6 1560.5
Alcohol-related disorders 1058; 6.9 319; 5.0 704; 10.4 20817.3
Substance-related disorders 411; 2.7 109; 1.7 240; 3.5 7602.7
Suicide and intentional self-inflicted injury 1472; 9.6 603; 9.4 918; 13.5 299310.5
Psychiatric Quarterly (2022) 93:791–802
Psychiatric Quarterly (2022) 93:791–802 797

About 37.0% (n = 10,564) of the hospitalizations with a primary diagnosis of depres-

sion were associated with other psychiatric comorbidities (as defined by CCS categories
650–661). The most frequent comorbidities were Personality Disorders (11.1%; n = 3,166),
followed closely by Suicide and intentional self-inflicted injury (10.5%; n = 2,993), alco-
hol-related disorders (7.3%; n = 2,081), and anxiety disorders (6.7%; n = 1,922) (Table 2).
Psychiatric comorbidities in depression related hospitalization varied between sexes.
The most prominent differences were found in Personality disorders (9.6%; 11.7% of male/
female episodes, respectively), Alcohol-related disorders (16.1%; 3.5% of male/female
episodes, respectively), Substance-related disorders (4.8%; 1.8% of male/female episodes,
respectively) and Suicide and intentional self-inflicted injury (13.3%; 9.3% of male/female
episodes, respectively).

Discussion

Depression related hospitalizations represented approximately one in five psychiatric hos-

pitalizations in Portugal, a similar value when compared to other countries (27.8%, USA,
where Stensland et al. selected more codes than the ones included in our study 298.0x,
301.12, 309.0x–309.1x— [18]). In the northern region of Portugal, a previous report found
that depression was the second most frequent cause of psychiatric emergency department
visits [19]. As depression is one of the largest factors contributing to global disability [20,
21] our findings confirm hospitalizations as important indicators of the burden of depres-
sion in patients’ lives and health services.
MDD accounts for most of the hospitalizations with a main diagnosis of depression,
which may be partially explained by its chronic and relapsing nature [4, 22]. Patients
with dysthymia are usually less severely depressed at initial examination [23] and do
not meet admission criteria as usually as patients with MDD. A recent Global Burden
of Disease (GBD) study described Portugal as one of the countries where the diagnosis
of dysthymia has increased between 1990 and 2017 [22]. Nevertheless, our data shows
a decrease in dysthymia related hospitalizations during the study period which might
translate the increasing availability of outpatient services, being inpatient care pro-
vided for more severe forms of depression (as MDD). This same study refers that dys-
thymia accounts for 6.3% of cases of depression in 2017, a lower value when compared
to the 22.4% of depression related hospitalizations found in our study. The registry
of Depression unspecified (code 311) as primary diagnosis represents all depressive
episodes that did not meet criteria for Dysthymia or MDD. This diagnosis may occur
in episodes in which the registries level of clinical detail does not provide appropriate
medical information for a specific diagnosis of Dysthymia or MDD, or in depressive
related episodes where these latter diagnoses do not apply, leading to a more heterog-
enous group of depression related episodes.
The study of seasonality in mood disorders is considered fragmented and in need
of more high-quality and unbiased studies on seasonal variation [24]. Our data shows
a clear tendency of a lower number of admissions due to MDD and other forms of
depression in December (holidays and religious festivities in December may explain
this trend) and a peak in March, as found in a recent Austrian study [25]. All sub-
types of depression had more episodes associated with the female sex, which might be
explained by the higher rate of depression related hospitalization in female sex patients
also found in other studies [26, 27]. Dysthymia was the diagnosis with the highest

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frequency of episodes linked to female sex patients (8 in 10 patients), with a more pro-
nounced discrepancy than MDD.
In Portugal, depression related hospitalizations present long LoS, particularly MDD
with a median longer LoS. When compared to other countries, Portugal (with a median
LoS of 13.0 days) stays in the middle of other countries’ average LoS (5.0 days in USA
[4]; 12.9 days in Italy [28]; 24.5 days in Ethiopia [29]; 33.4 days in China [30]). The dif-
ferences found might be explained by differences in patient selection and specific charac-
teristics of the health systems (co-payment methods; insurance vs. public financed sector)
[4]. Moreover, Portugal presents lower mean hospitalization charges when compared to the
USA ($6700-$8400) [4], even considering the higher median LoS.
It is estimated that 12% of MDD patients have at least one hospitalization episode
throughout their life, suicidal ideation and behaviour arise as one of the main motives
of admission [4, 5]. In Portugal only 10.5% of the episodes were linked to Suicide and
self-inflicted injury or suicidal ideation (E950-E959; V62.84), a lower value than would
be expected. Depression related hospitalizations also registered a lower value of comorbid
diagnosis of anxiety and substance use disorders when compared to Citromeet al. This dis-
crepancy might be explained by the heterogeneous codification of suicidal ideation across
medical registries and underreporting of suicidal behaviours/ideation.
Personality disorders are commonly diagnosed in patients with depression [31],
and in our study they were the most commonly registered psychiatric comorbidities
among patients hospitalized with depression. Citromeet al. found similar frequencies
(7.8–14.7%, in Truven MarketScan® Research Database and Premier Perspective®
Hospital Database), even if in a different relative order (6th most frequent psychiatric
comorbidity).

Strengths and Limitations

Real-World Evidence generated from administrative databases provides valuable and

generalized information about mental disorder related hospitalizations.
In Portugal all codifiers are medical doctors with specific training, ensuring a high-
quality registry. Nevertheless, codifiers depend on the clinical accuracy and documenta-
tion from other clinicians to perform a rigorous register. The methodological process
for obtaining the estimated number of patients has a very specific and low impact limi-
tation once the patients may have altered their residence during the study period and
count as more than one patient.

Conclusions

Depressive disorders are one of the leading causes of hospitalization in Portuguese psy-
chiatric departments, being responsible for approximately 1 in 5 hospitalizations with a
psychiatric diagnosis in the country. Portugal presented a mean hospitalization rate of
35.5 admissions per 100,000 inhabitants and most patients were female with a mean age
of 50.6 years.
To the best of our knowledge, this is the first longitudinal study that globally evalu-
ated Depression in Portugal and one of the few that analyses a nationwide inpatient

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setting. The use of a large database that contains all hospitalization episodes occurring
in Portuguese public hospitals allows to better describe and characterize patients with
depression in Portugal throughout an 8-year period. The use of Secondary Data in Men-
tal Health research allows us to draw a more detailed perspective on Depression related
healthcare. By defining the population with Depression this study gives a clear perspec-
tive on who are these patients, their clinical and sociodemographic characteristics. Cli-
nicians and policymakers may use the results and conclusions of this study to better
adjust therapeutic and health management targets.

Acknowledgements This project was approved by the Faculty of Medicine of the University of Porto Ethics
Committee (nº 16/CEFMUP/21).

Authors’ Contributions Author Manuel Gonçalves-Pinho designed the study and participated in all phases
of the study. Author João Pedro Ribeiro and Lia Fernandes participated in the clinical analyses and writing
of the paper. Authors Manuel Gonçalves-Pinho and Alberto Freitas undertook the statistical analysis, and
author Manuel Gonçalves-Pinho wrote the first draft of the manuscript. All authors contributed to and have
approved the final manuscript.

Funding This work was financed by FEDER—Fundo Europeu de Desenvolvimento Regional funds through
the COMPETE 2020—Operacional Programme for Competitiveness and Internationalisation (POCI), and
by Portuguese funds through FCT—Fundação para a Ciência e Tecnologia in the framework of the project
POCI-01–0145-FEDER-030766 (“1st.IndiQare—Quality indicators in primary health care: validation and
implementation of quality indicators as an assessment and comparison tool”). This article was supported by
National Funds through FCT—Fundação para a Ciência e a Tecnologia,I.P., within CINTESIS, R&D Unit
(reference UIDB/4255/2020).

Availability of Data and Material Data was provided by ACSS—Administração Central do Sistema de Saúde
I.P upon formal request.

Code Availability The authors used IBM SPSS Statistics v.25 for Windows (Armonk, NY: IBM Corp) for
statistical analysis.

Declarations
Informed Consent No informed consent was needed once we used an administrative database built for hos-
pital billing with no access to patients’ identification.

Research Involving Human Participants and/or Animals The data used was given by a Portuguese govern-
mental agency guaranteeing all identification information was anonymous. This project was approved by the
Faculty of Medicine of the University of Porto Ethics Committee (nº 16/CEFMUP/21).

Conflicts of Interest/Competing Interests The authors declare no conflicts of interest.

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Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and
institutional affiliations.

Manuel Gonçalves‑Pinho is an Invited Assistant at Faculty of Medicine, University of Porto and a psychia-
try resident at Centro Hospitalar do Tâmega e Sousa. He is a member of the research unit CINTESIS (cin-
tesis.eu), belonging to the 2D4H group (Secondary Data for Healthcare Research), and has been involved in
projects in several areas of health data science, including health information systems, data quality, intelli-
gent data analysis, performance and quality indicators, coding and audit. He is a Board member of the North
Regional Council of the Portuguese Medical Association.

João Pedro Ribeiro is a Psychiatrist working in the Inpatient Team in an Acute Psychiatric Ward at Centro
Hospitalar do Tâmega e Sousa, responsible for the mental health care of a geographical region of 500.000
inhabitants.

Lia Paula Nogueira Sousa Fernandes is a Psychiatrist Senior Graduate Assistant in the Psychiatry Service
of Centro Hospitalar Universitário São João (CHUSJ), with Geriatric Competency (OM) and Board Mem-
ber of this Portuguese Medical Association. Family Therapist by SPTF. PhD, Associate Professor with
Aggregation in the Department of Clinical Neurosciences and Mental Health of Faculty of Medicine—
University of Porto(FMUP). Member of Directive Council of Faculty of Medicine of University of Porto
(2018–2022). Director of Department of Clinical Neurosciences and Mental Health of FMUP (since 2022).
Researcher in the Center for Research in Health Technologies and Services (CINTESIS.UP), being PI of
GeriMHealth group. In charge of Psychiatry and Mental Health (Clinical Practice) of 6th year of the Master
Degree in Medicine. Is Director of the Master’s Degree in Psychiatry and Mental Health of FMUP, as well
as Coordinator of Geriatrics Post-Graduation of FMUP. She collaborates on Mental Health in Elderly of
PhD Programme of Gerontology and Geriatrics—UP/UA and had been teaching also in several universities
of Psychology, Nursing and Social Education, as well as in Post-graduation for General Practice. Portu-
guese Association of Gerontopsychiatry/APG (President 2010–13); International Psychogeriatric Associa-
tion/IPA (Board of Directors 2011–14 and 2020–22); European Association of Geriatric Psychiatry/EAGP
(Board since 2018); Dementia Cerebral Aging Group Study/GEECD (Board of Directors 2008–10); Portu-
guese Society for Geriatrics and Gerontology/SPGG (Scientific Board since 2012); Portuguese Society of
Family Therapy/SPTF (National Board 1997–00 and 2000–03); International Family Therapy Association/
IFTA (Board of Directors 2009–12 and 2012–15). She is the Clinical Director at the North Regional of the
Association for the Support of Depressive and Bipolar Patients (ADEB). Researcher member of interna-
tional networks: INTERDEM/Early, Timely and Quality Psychosocial Interventions in Dementia, EHDN/
European Huntington’s Disease Network, IBERDEM/Iberoamerican Centre of Research in Prevention and
Rehabilitation of Alzheimer and Other Dementias, AGE Platform Europe and Porto4Ageing consortium –
Oporto Excellence Centre on Active and Healthy Ageing.

Alberto Freitas is an Assistant Professor at Faculty of Medicine, University of Porto. In 2007 he achieved
the PhD degree at the School of Economics and Management of the University of Porto, Portugal, with a
thesis on the use of data mining techniques for the analysis of hospital inpatient databases. He is member
of the research unit CINTESIS (cintesis.eu), with the coordination of the 2D4H group (Secondary Data for
Healthcare Research), and has been involved in projects in several areas of health data science, including
health information systems, data quality, intelligent data analysis, performance and quality indicators, cod-
ing and audit. He has lectured several disciplines on Biostatistics, Hospital Management, and Medical Infor-
matics of pre- and post-graduation courses. He is former director of a master in health informatics (mim.
med.up.pt).

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802 Psychiatric Quarterly (2022) 93:791–802

Authors and Affiliations

Manuel Gonçalves‑Pinho1,2,3 · João Pedro Ribeiro3 · Lia Fernandes2,4,5 ·

Alberto Freitas1,2
1
Department of Community Medicine, Information and Health Decision Sciences, Faculty
of Medicine, University of Porto, Porto, Portugal
2
Center for Health Technology and Services Research (CINTESIS), Porto, Portugal
3
Department of Psychiatry and Mental Health, Centro Hospitalar Do Tâmega E Sousa, Penafiel,
Portugal
4
Department of Clinical Neurosciences and Mental Health, Faculty of Medicine, University
of Porto, Porto, Portugal
5
Psychiatry Service, Centro Hospitalar Universitário de São João, Porto, Portugal

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