For general practitioners (GPs), it may be challenging to assess suicidal ideation (SI) in patients. Although promising instruments exist for the use in primary care, only a few have been validated in German. The objectives of this study were to examine the validity of the brief P4 screener for assessing SI in a cross-sectional study including outpatients. Inclusion criteria were a PHQ-9 score ≥ 10 or an affirmative answer to its SI item. Construct validity of the P4 was examined by comparison with the four-item Suicide Behaviors Questionnaire-Revised (SBQ-R), the PHQ-9 (convergent), and the positive mental health (PMH) scale (divergent). The study sample included 223 patients (mean age 47.61 ± 15 years; 61.9% women) from 20 primary care practices (104 patients) and 10 psychiatric/psychotherapeutic clinics (119 patients). The first three items of the P4 correlate positively with most of the four items of the reference standard SBQ-R (convergent validity); the fourth item of the P4 (preventive factors) correlates significantly with the PMH scale. The most common preventive factor (67%) is family or friends. The German P4 screener can be used to assess SI in outpatient care. It explores preventive or protective factors of suicide, which may support the GP's decision on treatment. We recommend a further clinical interview for patients flagged by P4 assessment in order to more formally assess suicidal risk.
Keywords: primary care; psychometric evaluation; suicidal behavior screener; suicidal ideation; suicide prevention.