Mapping of mental health indicators in the WHO European region: a scoping review

Abstract

Objective

This scoping review aims to map and describe mental health indicators used in peer-reviewed studies in the WHO European Region to inform the development of a regional mental health measurement framework.

Methods

reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Review (PRISMA-ScR), this scoping review analysed 75 studies identified through database searches on mental health monitoring and indicators in the WHO European Region. The scope was restricted to English-language, peer-reviewed literature published from 2019 onwards. Indicators were extracted and standardised to reflect their original reported meaning, treated as distinct and pragmatically classified into nine predefined domains.

Results

Across the 75 studies, 450 distinct indicators were identified. Most indicators related to mental health status and mental health risk factors and/or determinants. Geographic coverage varied, with northern and western European countries most frequently represented among the included literature. Diverse measurement tools were employed.

Discussion

The predominance of indicators related to mental health status and determinants reflects the emphasis on burden and underlying factors, while system-level or structural indicators remain under-represented. Differences in geographic coverage likely stem from disparities in research capacity, publication practices and data availability.

Conclusions

This scoping review provides a descriptive overview of mental health indicators applied in recent peer-reviewed research in the Region. Greater alignment between research indicators and policy frameworks may strengthen the comparability and policy utility of mental health data across the Region.

WHAT IS ALREADY KNOWN ON THIS TOPIC.

WHAT THIS STUDY ADDS

• This study maps 450 distinct mental health indicators from peer-reviewed studies in the WHO European Region. It identifies a predominant focus on mental health status and risk factors, with limited attention to system performance and quality-of-care indicators. Geographic representation is uneven, reflecting disparities in research coverage and data availability.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

• This study maps mental health indicators used in peer-reviewed studies across the WHO European Region, providing a structured overview to inform the development of a coherent regional mental health measurement framework. Strengthening alignment between research outputs and policy priorities can enhance comparability, identify critical evidence gaps and support coordinated evidence-informed regional action.

Introduction

Good mental health and well-being are fundamental to overall health and a critical dimension of public health. They influence individual functioning and quality of life, as well as societal cohesion, productivity and resilience. Mental health is increasingly recognised as a public health priority, particularly within the WHO European Region. Over 143 million people in the region live with some form of mental health condition, accounting for 16% of the population in 2021.¹ These numbers increased significantly during the COVID-19 pandemic, with an estimated increase in prevalence of 25% compared with prepandemic levels in 2019.² The pandemic also underscored the importance of timely and reliable mental health data, revealing critical information gaps that hinder rapid policy response and service delivery planning, as well as the effective use of mental health indicators in research and decision-making.

Over the past decade, there has been growing recognition of the need for robust mental health monitoring systems, supported by standardised, valid and policy-relevant indicators.³ These indicators play an important role in tracking service availability, identifying unmet needs, guiding reforms and evaluating the impact of mental health interventions, thereby supporting accountability and evidence-based policymaking.⁴ However, despite this momentum, there remains wide variation in how indicators are defined, selected and used. This diversity is understandable, given differences in national priorities, data infrastructure and research objectives across countries. Yet, without consistent use of mental health indicators, it becomes difficult to assess progress over time, compare findings across settings or evaluate the effectiveness of system-level interventions.

Population health monitoring increasingly relies on indicators derived from diverse data sources, such as health surveys and administrative registers, each differing in scope, application and comparability.⁵ These indicators are applied differently across studies; some prioritise service coverage or clinical outcomes, while others focus on population-level burden or determinants of mental health. Without a clear methodological framework for defining and applying indicators, inconsistencies arise that make it difficult to accurately measure trends, compare findings across studies and integrate results into policy discussions.

While frameworks such as the WHO European Framework for Action on Mental Health 2021–2025 and the Organisation for Economic Co-operation and Development’s indicators offer valuable guidance for monitoring mental health and well-being, alignment with these frameworks appears limited in the peer-reviewed literature.^{4 6} This limits opportunities for cross-country comparison, policy monitoring and consistent assessment of mental health system performance. In Germany, for example, the Robert Koch Institute developed a Mental Health Surveillance (MHS) system proposing a structured set of indicators for national monitoring⁷ and Peitz et al conducted a scoping review to inform surveillance development in Germany.⁸

Beyond Germany, several scoping reviews, feasibility studies and indicator mappings have examined mental health indicators within specific populations, domains or sub-regional contexts or through normative frameworks rather than empirical mapping of peer-reviewed literature across the WHO European Region.^{9 10} However, region-wide insights into how mental health indicators are applied across peer-reviewed studies remain limited, hindering consistent monitoring, cross-country comparison and policy learning aligned with European mental health frameworks.⁴

Informed by the work of Peitz et al, this scoping review aims to systematically map and describe the landscape of mental health indicators used in peer-reviewed studies since 2019 in the WHO European Region. By providing a comprehensive descriptive overview of how these indicators are applied in the literature, this work complements existing national and framework-driven efforts and informs the development of a regional mental health measurement framework.

Methods

Protocol and reporting

This scoping review is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Review (PRISMA-ScR).¹¹ A formal review protocol was not publicly registered; however, core methodological parameters, including the review objectives, eligibility criteria, database selection and search limits (English-language publications from 2019 onwards), were defined a priori to study identification and screening. Analytic decisions related to the organisation and synthesis of indicators were refined iteratively following study selection, in keeping with the exploratory aims of scoping reviews.

Search strategy

To scope the peer-reviewed literature on mental health indicators in the WHO European Region, three databases were searched: PubMed, Embase and PsycINFO. PubMed and Embase were selected to ensure comprehensive coverage of biomedical and public health research, while PsycINFO was included to capture specialised literature on mental health studies.

Given the objective of mapping mental health indicators rather than identifying all possible eligible studies, database searching was considered sufficient for the purposes of this review, and additional reference list searching was not conducted.

The search was conducted on 9 January 2025, and reflects the peer-reviewed literature available up to that date. Given that this review specifically targets indicators applied in nationally representative monitoring and established surveillance systems, which are underpinned by large-scale data infrastructures (such as national registers and health surveys) that evolve over multiyear policy and monitoring cycles, this search date was considered to provide adequate currency to reflect the landscape of the Region.

The search strategy drew on the approach outlined by Peitz et al and was refined in collaboration with a scientific information specialist.⁸ The search combined controlled vocabulary and free-text terms related to mental health and mental illness, monitoring and surveillance and population-level indicators. To ensure technical rigour and reproducibility, the electronic search strategy was peer-reviewed prior to execution using the Peer Review of Electronic Search Strategies (PRESS) checklist.¹² While supplementary hand-searching of reference lists or forward citation chaining was not performed, the PRESS-validated strategy yielded a broad initial pool of 7743 records, providing broad coverage of the peer-reviewed literature and reducing the likelihood of missing seminal references. The complete search strategies for each database are provided in online supplemental file 1.

Articles were limited to those published in English from 2019 onwards. The 2019 cut-point was established a priori to build directly on the foundational indicator mapping conducted by Peitz et al,⁸ thereby avoiding methodological redundancy while enabling a comprehensive mapping of more recent developments at the time of study execution. This approach aligns with the scoping review aim of broadly characterising indicator use, rather than exhaustively re-mapping earlier evidence.

Eligibility and selection criteria

All retrieved records were deduplicated using EndNote and imported into Rayyan.ai for title and abstract screening.¹³ The screening and data extraction were conducted independently by four reviewers, with disagreements resolved by a fifth designated referee (see online supplemental file 1).

The eligibility criteria were defined a priori, finalised before title and abstract screening commenced, and remained unchanged throughout the review. During development of the search strategy, search terms were refined iteratively in collaboration with a scientific information specialist to improve search sensitivity and ensure that relevant studies were captured. This iterative refinement applied only to the search strategy and did not alter the predefined eligibility criteria.

Studies were included if they were primary research or systematic reviews of population studies; focused on mental health indicators, monitoring, or surveillance at the national or federal level in one or more of the 53 WHO European Region Member States¹⁴; addressed the general population across any life stage; and reported outcomes related to mental health status, determinants or system performance.

Studies were excluded if they focused exclusively on subnational areas, specific non-age-related populations (such as people with cancer, pregnant women, or key workers), or examined mental health solely in the context of time-limited events like pandemics or conflicts. Studies on clinical interventions, policy evaluations, tool validation, or those treating mental health solely as a determinant of other outcomes were also excluded. Narrative reviews, case studies, and editorials were not eligible. A full list of inclusion and exclusion criteria is provided in online supplemental file 1.

Data extraction and indicator mapping

To structure the analysis, extracted indicators were grouped into nine predefined domains (online supplemental table 1) reflecting key areas of mental health measurement. These domains were aligned with previous frameworks⁶ and were applied pragmatically based on the nature of the indicators reported in the included studies. For domains where a large number of indicators were identified, further subgroups were created inductively to facilitate organisation and analysis.

Each indicator was treated as distinct based on how it was reported in the original studies. This approach preserved the diversity in terminology, measurement tools, and conceptual framing found in the peer-reviewed literature. Indicators with different names, slight variations in wording or those reported at different time points within the same study were counted separately when presented as such by the original authors. Where studies presented composite measures or grouped indicators, these were reflected accordingly in the extraction.

Quality appraisal was not conducted to ensure inclusivity and comprehensive literature representation as the focus was on mapping the range of mental health indicators reported rather than evaluating the methodological rigour or validity of individual studies.

Results

Study selection

A total of 75 articles, published from 2019 onwards, were included in this review. The initial search yielded 7743 records. After deduplication and limiting to eligible publication years, 2270 records remained for screening. Following title and abstract review, 180 full-text articles were assessed for eligibility, of which 75 met all inclusion criteria, as detailed in the PRISMA flow diagram (figure 1).

Figure 1. PRISMA flow chart. PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

Geographic distribution of included studies

The included studies covered 35 of the 53 countries in the WHO European Region. The countries with the highest number of included studies were Denmark, the UK, the Netherlands, Sweden and Germany. In total, 18 of the 35 countries were represented only through multicountry studies (figure 2).

Figure 2. Study distribution by country*. *For the purposes of figure 2 and related analyses, the UK and its constituent countries (England, Scotland, Wales and Northern Ireland), as well as the region of Great Britain (England, Scotland and Wales), are presented as separate entities. This reflects the way study populations were defined and reported in the included literature. In the overall country count reported in the main text, however, the UK is treated as a single country in line with WHO classification.

Characteristics of included studies

Covered populations in the selected studies (individual publications) spanned various life stages, with the majority (31 studies; 42%) focusing on adults, and 16 studies (22%) including children and/or adolescents. The most commonly used measurement tool across included studies was the Composite International Diagnostic Interview 3.0 (Diagnostic and Statistical Manual of Mental Disorders IV-based), followed by International Classification of Diseases-coded diagnoses, self-reported measures, the General Health Questionnaire-12 and the Patient Health Questionnaire-8/9). Other frequently used instruments included the Strengths and Difficulties Questionnaire, the Mini International Neuropsychiatric Interview and the Warwick-Edinburgh Mental well-being Scale.

Indicator mapping and domain distribution

The 450 indicators extracted from the included studies were classified into nine predefined mental health domains (see online supplemental table 1), with the majority of indicators falling under the domains of mental health status (260 indicators; 58%) and mental health risk factors and/or determinants (113 indicators; 25%) (table 1). The remaining domains including positive mental health, mental healthcare utilisation, mental healthcare resources, pharmaceutical consumption and/or sales, mental healthcare outcomes, mortality and quality of mental healthcare, contributed smaller proportions of the total indicators.

Table 1. Distribution of indicators by domain.

Domains	Distinct count of indicators	Distinct count of indicators (%)
Mental health status	260	58
Mental health risk factors/determinants	113	25
Positive mental health	20	4
Mental healthcare utilisation	19	4
Mental healthcare resources	16	4
Pharmaceutical consumption/sales	10	2
Mental healthcare outcomes	7	2
Mortality	5	1
Quality of mental healthcare	3	1
Total distinct indicators	450*	100

^*Across the datasets reviewed, we identified 453 distinct indicators. Note that three indicators (prevalence of anxiety, depression and eating disorders) fall under two domains, that is, mental health status and mental health risk factors and/or determinants, because they were used to capture different aspects of mental health in different studies. When counting unique indicators, 450 distinct indicators were observed overall.

Subgrouping within key domains

Given the large number of indicators identified in the domains of mental health status and mental health risk factors and/or determinants, further classification into pragmatic subgroups was undertaken to facilitate analysis. These subgroups reflected broad diagnostic categories, population characteristics, or key determinant areas as defined by the content of the included indicators (table 2). Full details of all distinct indicators and their study references, along with their classification by domain and, where applicable, subgroup, are provided in online supplemental table 2.

Table 2. Distribution of indicators within the mental health status and mental health risk factors and/or determinants domains.

Domains and subgroups	Distinct count of indicators
Mental health status
Common mental disorders	72
Neurodevelopmental and other disorders	56
General mental health symptoms and functioning	52
Substance use disorders	24
Eating and obsessive–compulsive disorders	18
Psychotic disorders (including schizophrenia)	14
Personality disorders	10
Disruptive and behavioural disorders	9
Self-harm and suicidal behaviour	5
Mental health risk factors/determinants
Sociodemographic factors	27
Psychological and behavioural factors	25
Environmental factors	21
Family and social support	16
Physical and lifestyle factors	13
Trauma and abuse	11

Descriptive analysis of indicators

Within the mental health status domain, the majority of indicators fell under three key subgroups: common mental disorders, neurodevelopmental and other disorders and general mental health symptoms and functioning (table 2). The most prominent themes within the common mental disorders subgroups included indicators related to depression, followed by anxiety, mixed and other common mental disorders and mood disorders. Neurodevelopmental indicators primarily reflected themes around intellectual and developmental disorders, attention-deficit/hyperactivity disorder and autism spectrum disorder. Additional indicators captured broader population-level burden and functional symptoms.

The mental health risk factors and/or determinants domain was similarly structured into subgroups. Notable themes included indicators reflecting sociodemographic factors particularly socioeconomic status, as well as psychological and behavioural factors and environmental factors such as exposure to pollution, urban living conditions and access to green and blue spaces. Several indicators were also classified under themes related to family and social support, physical and lifestyle factors and trauma and abuse.

For the remaining domains, which included mental healthcare utilisation, pharmaceutical consumption and/or sales, quality of mental healthcare, mental healthcare outcomes, mortality and positive mental health, indicators were fewer in number and grouped into one or two key themes each. For example, most indicators under mental healthcare utilisation related to specific types of services or treatments, while those in the pharmaceutical consumption and/or sales domain focused on prevalence and prescribing patterns of psychotropic medication. Indicators under positive mental health primarily captured aspects of well-being, flourishing and quality of life. See online supplemental table 2 for the complete list of distinct indicators and their study references, along with their classification by domain, subgroup and theme (where applicable).

To complement the overall mapping, an exploratory descriptive analysis examined the distribution of distinct indicators across domains for countries represented in the included studies. This analysis is intended to be illustrative of patterns in the peer-reviewed literature and not to support cross-country comparison or assessment of national indicator coverage. Full details are provided in online supplemental table 3.

Discussion

Measuring mental health at the population level presents inherent challenges due to the subjective nature of mental health experiences, cultural variation in symptom expression and the evolving conceptualisation of mental well-being. These challenges were reflected in the high number of distinct indicators identified in this review, especially in domains such as mental health status and risk factor and/or determinants.

The absence of universally accepted definitions or measurement tools for some constructs may further contribute to the observed diversity in indicators. These challenges highlight the need for flexible yet comparable approaches to MHS that can accommodate population diversity while enabling consistency and comparability.

A prominent pattern emerging from this mapping was the strong emphasis on indicators of mental health status and risk factors/determinants, alongside comparatively fewer indicators addressing system-level performance, quality of care or service outcomes. This pattern should be interpreted with caution, as it reflects reporting in peer-reviewed literature rather than the full scope of national monitoring infrastructures or routine health system data collection. While it may partly stem from the review’s scope and inclusion criteria, the relative scarcity of system-level and quality-oriented indicators in the peer-reviewed literature nonetheless suggests an important area for future work.

The geographic distribution of included studies showed greater representation from Western and Northern European countries. This likely reflects differences in research capacity, publication practices and access to routinely collected data suitable for analysis within peer-reviewed English-language studies, rather than true differences in the scope or maturity of national mental health monitoring systems. As this review did not examine grey literature, national statistical reports or administrative surveillance outputs, no inferences can be made regarding the completeness or quality of country-level monitoring efforts. The country-level distributions presented should therefore be viewed as illustrative of peer-reviewed research rather than as indicators of national performance or coverage.

This review complements earlier work by Peitz et al, which mapped mental health indicators to inform the development of a national surveillance system in Germany, by extending a similar descriptive approach across peer-reviewed studies from multiple countries within the WHO European Region.⁸ In contrast to framework-driven or policy-oriented indicator initiatives, this review was explicitly grounded in empirical research practice, focusing on how indicators are operationalised in published studies rather than on normative recommendations. In doing so, it provides a region-wide descriptive reference that complements existing national initiatives and international frameworks, including those led by WHO and the OECD, without duplicating their objectives.^{4 6}

A key strength of this scoping review is its systematic and transparent mapping of mental health indicators used in recent peer-reviewed research across the WHO European Region. By documenting how indicators are defined, applied and grouped, the review provides a descriptive foundation to improve coherence, comparability and transparency in mental health monitoring. The identified patterns can inform efforts to better align research practices with policy-oriented measurement frameworks and strengthen the utility of mental health data for regional learning and decision-making.

Several methodological limitations should be acknowledged when interpreting these findings. The review was restricted to English-language peer-reviewed literature published from 2019 onward and did not include grey literature or routine surveillance outputs, which may have resulted in underrepresentation of some indicators, domains or countries. In addition, the exploratory country-level analyses are influenced by publication volume and study design rather than national monitoring capacity.

Conclusions

This scoping review undertook a descriptive mapping of mental health indicators within peer-reviewed literature from the WHO European Region published between 2019 and 2024. By extracting and classifying 450 distinct indicators into nine predefined domains, this review highlights the diversity of indicators applied in recent research, with a predominant focus on individual mental health status and associated risk factors. It also underscores the variability in geographic coverage and measurement approaches across studies, providing a timely overview of current research practices in the region.

Importantly, this review offers a descriptive reference for researchers and public health practitioners interested in the types of indicators currently used in peer-reviewed mental health research. It also highlights the need for greater standardisation of mental health indicators across research and policy systems in the WHO European Region. Future research should prioritise alignment between research-generated indicators and national measurement frameworks to improve comparability and policy translation.

The author is a staff member of the World Health Organization. The author alone is responsible for the views expressed in this publication and they do not necessarily represent the views, decisions or policies of the World Health Organization.

The authors affiliated with the World Health Organization (WHO) are alone responsible for the views expressed in this publication and they do not necessarily represent the decisions or policies of the WHO.

Data availability statement

Data sharing not applicable as no datasets generated and/or analysed for this study.