Hoekstra 2006.

Study characteristics
Methods	Randomised trial, the Netherlands
Participants	146 patients with cancer in the palliative phase
Interventions	Symptom reporting with a systematic symptom monitoring instrument (Symptom Monitor).   Intervention features Multiple simple feedback (one PROM at multiple times) PROM(s) used as intervention: Symptom Monitor (assessing 10 symptoms) Constructs measured: Symptoms Instrument categories/domains: Domain/Disease specific (cancer)   Administration features Where PROMs administered: Non‐clinical setting How administered: Self‐administered Format of PROMs questionnaire(s): Paper   Feedback features Format of PROMs feedback: Paper How often information fed back: Weekly Who information fed back to: Clinicians Information fed back: Scores
Outcomes	Main outcome: prevalence and severity of symptoms (Symptom Monitor)
Notes	The study was funded by the Dutch Cancer Society (grant). The study recruited between January 2000 and June 2002. Conflicts of interest were not reported.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Block design (randomisation by GP practice)
Allocation concealment (selection bias)	High risk	Patients knew their allocation and so did the therapist in the intervention group
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible due to study design.
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	Low risk	Tables 2 and 3 compare the prevalence and symptom severity scores at baseline between groups which are similar
Baseline characteristics similar	Low risk	Table is provided and paper states that the baseline characteristics were quote "distributed equally in terms of age and gender between the two groups".
Incomplete outcome data (attrition bias) All outcomes	Low risk	The study group expected a high dropout rate due to death and analysis was done separately for complete datasets
Was study protected against contamination	Low risk	Randomisation by GP practice.
Selective reporting (reporting bias)	Unclear risk	Unclear whether selective reporting took place