Abstract

Background
General practitioners play a pivotal role in the diagnosis attention-deficit/hyperactivity disorder (ADHD) in adults. This systematic review aims to determine the effectivity and feasibility of screening tools for ADHD in adults in primary care.

Method
A literature search was performed in PubMed, Cochrane Library, Ovid, ERIC, PsycInfo, PSYNDEX and Embase in November 2022. Sensitivity and specificity were considered as primary outcomes. Further psychometric properties, feasibility in general practice as well as digital practicability were evaluated as secondary outcomes. Risk of bias was assessed via QUADAS-2/C. A narrative data synthesis and meta-analysis was performed (PROSPERO: CRD42022374597).

Results
A total of fifty-eight studies were included in data analysis. These studies referred to eighty-four various screening tools. ASRS-6 (DSM-V), WURS-25, CAARS-s:sV and TRAQ10 are suitable instruments for screening of ADHD in adults in primary care. The highest test accuracy was shown by ASRS 6 (DSM-V) (Sensitivity=0.83 [0.67–۰٫۹۲], Specificity=0.87 [0.93–۰٫۸], AUC=0.92, I2=8.6–۱۲٫۳ %).

Limitations
Included studies used rating scales as reference standard. Some studies compared study groups to control groups with an unknown ADHD status and there is a large degree of heterogeneity between the populations. Some studies referred to the best-balanced results of sensitivity and specificity under a certain cut-off, that has not been determined before.

Conclusion
Feasibility studies are needed to provide more evidence for WURS-25 and CAARS-s:sV. The determination of sufficient cut-offs is important, to improve the identification of ADHD in adults by general physicians.

Introduction

Attention-deficit/hyperactive disorder (ADHD) according to the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5) and hyperkinetic disorder (F90) or attention deficit without hyperactivity (F98.8) according to the International Classification of Diseases, editions 10 and 11 (ICD-10/11)) is commonly known as a childhood disorder which is characterized by altered hyperactivity, inattention and impulsivity (Drechsler et al., 2020). These symptoms persist until adulthood in about 50 % of all diagnosed patients (Sibley et al., 2017, 2022). Moreover, patients show characteristic features, which include executive dysfunction, disorganization and emotional distress, leading to an impairment of their daily lives (Barkley, 1997; Wender, 1998). Common comorbidities are depression, borderline personality disorder, social phobia, anxiety, or substance abuse (Fayyad et al., 2017; Kessler et al., 2006). Although a prevalence of approximately 2–۳ % of ADHD in adults is estimated, only 0.2–۰٫۴ % are actually diagnosed in Germany (Fayyad et al., 2017; Bachmann et al., 2017; de Zwaan et al., 2012). A possible reason seems to be a gap in medical care for young adults in a time of transition after leaving the pediatric setting (Eklund et al., 2016; Robb and Findling, 2013). Moreover, ADHD might be masked by other psychiatric symptoms and comorbidities (Retz et al., 2013). A missing or failed diagnosis prevents access to optimal medical care in the form of an evidence-based treatment of affected adults. General practitioners are considered to act as so-called „gatekeepers“, a role that is characterized by the initial identification of patients (Kwon et al., 2023; French et al., 2020). Consequently, there is a distinct need for appropriate diagnostic tools in primary care, as has already been identified in relevant guidelines (Eom and Kim, 2023; National Institute for Health and Care Excellence: Guidelines, 2018). There are many different screening tools, which differ in relevant aspects of the disorder. Some screening tools evaluate childhood symptoms, whereas others focus on current adult symptoms. Some screening tools are based on DSM-5 criteria, others on Utah criteria or no specified criteria. They differ in time or way of application, number of items, and scoring methods. For example, the choice of cutoff scores in ADHD screening tools directly influences clinical decision-making, including the initiation of treatment interventions. A higher cutoff score may exclude individuals who, despite exhibiting significant symptoms, do not meet the stringent criteria, potentially denying them access to necessary interventions. Conversely, a lower cutoff score could lead to the inclusion of individuals with mild symptoms, leading to over-treatment. The variability in cutoff points complicates the determination of treatment eligibility, potentially affecting the efficacy and efficiency of ADHD management strategies. Until, there is no comprehensive overview of validated studies including a quantitative meta-analysis (Taylor et al., 2011). Therefore, the aim of the study was to evaluate screening tools for ADHD in adults, considering sensitivity, specificity and feasibility for primary care.

Conclusion

Our findings show that screening tools as the ASRS-6 (DSM-V), the WURS-25, the CAARS-s:sV and the TRAQ10 are suitable instruments for screening of ADHD in adults in primary care due to their high validity and perceived feasibility in this setting. The best evidence exists for the ASRS-6, which was included in our meta-analysis. For more evidence concerning feasibility of the WURS-25 as well as the CAARS-s:sV, which also were part of the meta-analysis, feasibility studies are required. Regarding other tests like the TRAQ10 with equivalent promising results but insufficient options of comparison there is a need of further validation studies to create more evidence in that part. The determination of cut-offs is of great importance since it affects the ability of a screening tool distinguishing between real and false positives respectively negatives. Further research is required to identify the optimal cut-off of the different tests for a general population sample as we find it in primary care. Hence, the identification of ADHD in adults by general physicians would be improved without leading to increased misdiagnoses.