De Jong 2014.

Study characteristics
Methods	Randomised trial, the Netherlands
Participants	475 adult patients, recruited from private psychotherapy practices and outpatient mental health institutions Mean age 38.2 YEARS (SD 12.0) Female 68%
Interventions	Patient progress in terms of symptom distress, interpersonal relations, and social role (OQ‐45)   Intervention features Multiple simple feedback (one PROM at multiple times) PROM(s) used as intervention: Outcome Questionnaire‐45 (OQ‐45) Constructs measured: Symptoms, Functioning Instrument categories/domains: Domain/Disease specific (mental health)   Administration features Where PROMs administered: Patients could log in anywhere, but most completed on laptop provided in therapist's waiting room How administered: Self‐administered Format of PROMs questionnaire(s): Electronic   Feedback features Format of PROMs feedback: Electronic How often information fed back: Each therapy session Who information fed back to: One intervention group clinician only, one intervention group clinicians and patients Information fed back: Scores, Previous scores, Interpretation guidance, Management recommendations
Outcomes	Main outcome: patient progress (OQ‐45)
Notes	The study was supported by The Netherlands Organization for Health Research and Development (grant# 94506414). The study period was from 1 July 2006 to 31 June 2011. Conflicts of interest were not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation using an online system
Allocation concealment (selection bias)	Unclear risk	Randomisation was done online so unclear as to whether participants or therapists knew of allocation
Blinding of participants and personnel (performance bias) All outcomes	High risk	Due to nature of intervention not possible to blind patients and personnel.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Due to nature of the intervention blinding of outcomes not possible: PROM used for feedback also used to assess outcome, patients were aware they received the intervention.
Baseline outcome measurements similar	High risk	Significant differences (P = 0.01) found between conditions.
Baseline characteristics similar	Low risk	None apparent.
Incomplete outcome data (attrition bias) All outcomes	High risk	High rates of attrition in both groups which was not adequately addressed
Was study protected against contamination	Unclear risk	Not clear what the control group had access to
Selective reporting (reporting bias)	Low risk	Outcomes mentioned in the methods were discussed in the results section