Clinical Trial Evidence on Suicide Risk Assessment and Prevention Strategies: An Analysis of Completed Studies Registered on ClinicalTrials.gov

Background/Objectives: Suicide remains a leading cause of preventable mortality across the globe, fundamentally representing a complex public health challenge requiring effective risk assessment and prevention strategies. Despite increasing research activity, evidence from clinical trials remains heterogeneous, notably with the effectiveness of available interventions substantially varying across populations and settings. Accordingly, a systematic evaluation of completed clinical studies is essential to clarify current research trends, intervention effectiveness, and existing evidence gaps in suicide prevention. Methods: In this descriptive analytical study, I reviewed completed interventional clinical trials from ClinicalTrials.gov that investigated suicide risk assessment tools, prevention strategies, and pharmacological and non-pharmacological interventions targeting suicidal ideation or behavior in adult populations, particularly individuals aged 18 years and above. Trials were identified using predefined eligibility criteria. Data were extracted on study design, populations at risk, intervention type, suicide-related outcome measures, and safety reporting. The initial search was done on 28 March 2026 for completed interventional studies using predefined search terms, and the findings were synthesized descriptively without quantitative pooling. Results: Eight completed interventional trials met inclusion criteria. Most studies were randomized controlled trials enrolling high-risk adult populations, including individuals with mood disorders, post-traumatic stress disorder, recent psychiatric hospitalization, or prior suicide attempts. Non-pharmacological interventions, particularly cognitive behavioral therapy, collaborative care models, safety planning, and digital or telehealth-based approaches, predominated. Validated suicide risk instruments such as the Columbia-Suicide Severity Rating Scale, Beck Scale for Suicide Ideation, and PHQ-9 item 9 were commonly used, though outcome designation and reporting completeness varied. Registry-reported findings suggested heterogeneous effectiveness across interventions, and safety reporting was inconsistent, with limited long-term data available. Conclusion: This registry-based analysis highlights important progress in suicide prevention research while revealing persistent methodological and reporting limitations. The greater standardization of outcome measures, improved result reporting, broader population inclusion, and longer follow-up are needed to strengthen the evidence base and inform effective clinical and policy decision-making in suicide prevention. However, and while registry-based findings show meaningful research activity, incomplete result-posting across several trials limits definitive conclusions regarding comparative efficacy, underscoring the need for improved reporting standardization.