Objective: Routine outcome monitoring (ROM) is applied in many physical and mental health treatments. The treatment course is monitored with patient reported outcome measures (PROMs). A potential problem with PROM is response burden. This can be decreased by presenting such measures with less and better selected items. The SCL-90-R is an often used PROM for psychotherapies and a number of very short forms have been developed; the SCL-5, SCL-8, SCL-9 and SCL-10. This study aims to develop a new very short form, the symptom checklist 3 out of 7 (SCL-3/7) and to evaluate the effectiveness of these PROM with the precision relative to the complete SCL-90-R score.
Methods: Item Response Theory analysis was applied to select the 7 best discriminating items, evenly distributed over the latent trait. A routing serves that patients only need to administer 3 items.
Results: In a sample of 15,055 cases, the relative precisions of the SCL-3/7 were best for outpatients (122.7%), day care patients (111.8%) and inpatients (108.3). The SCL-5 was best for juvenile patients (110.0%), and the SCL-9 was best for addicted patients (107.2%).
Conclusion: The SCL-3/7 decreases patient burden in ROM and has a better precision in adult therapies than other SCL-90 short forms.
Keywords: IRT analysis; SCL-90-R; patient reported outcome measures; response burden; routine outcome monitoring.
© 2022 The Authors. Acta Psychiatrica Scandinavica published by John Wiley & Sons Ltd.