Assessment of Biopsychosocial Complexity and Health Care Needs: Measurement Properties of the INTERMED Self-Assessment Version.

ABSTRACT

OBJECTIVE: The INTERMED Self-Assessment questionnaire (IMSA) was developed as an alternative to the observer-rated INTERMED (IM) to assess biopsychosocial complexity and health care needs. We studied feasibility, reliability, and validity of the IMSA within a large and heterogeneous international sample of adult hospital inpatients and outpatients as well as its predictive value for health care use (HCU) and quality of life (QoL). METHODS: A total of 850 participants aged 17 to 90 years from five countries completed the IMSA and were evaluated with the IM. The following measurement properties were determined feasibility by percentages of missing values; reliability by Cronbach α; interrater agreement by intraclass correlation coefficients; convergent validity of IMSA scores with mental health (Short Form 36 emotional well-being subscale and Hospital Anxiety and Depression Scale), medical health (Cumulative Illness Rating Scale) and QoL (Euroqol-5D) by Spearman rank correlations; and predictive validity of IMSA scores with HCU and QoL by (generalized) linear mixed models. RESULTS: Feasibility, face validity, and reliability (Cronbach α = 0.80) were satisfactory. Intraclass correlation coefficient between IMSA and IM total scores was .78 (95% CI = .75-.81). Correlations of the IMSA with the Short Form 36, Hospital Anxiety and Depression Scale, Cumulative Illness Rating Scale, and Euroqol-5D (convergent validity) were -.65, .15, .28, and -.59, respectively. The IMSA significantly predicted QoL and also HCU (emergency department visits, hospitalization, outpatient visits, and diagnostic examinations) after 3- and 6-month follow-up. Results were comparable between hospital sites, inpatients and outpatients, as well as age groups. CONCLUSIONS: The IMSA is a generic and time-efficient method to assess biopsychosocial complexity and to provide guidance for multidisciplinary care trajectories in adult patients, with good reliability and validity across different cultures.