Wurtele 1980

Methods	Randomised controlled trial with three groups.
Participants	Country: USA. Setting: other. Health problem: tuberculosis. Recruitment: adverts. Participants: students (n=1946).
Interventions	Contract features: Form: written; Parties: patients‐practitioners; Incentives: none; Co‐interventions: no. Group 1: participants were asked for both verbal and written commitment to return. Group 2: participants were asked for their verbal commitment to return for skin‐test reading in 48 hours. Group 3: participants were told to return to have skin test read 48 hours later.
Outcomes	Number attending for skin test reading.
Notes
Risk of bias
Item	Authors' judgement	Description
Allocation concealment?	Unclear	B ‐ Unclear

NA: information not available; PHC: Primary Health Care.

The number of participants reflects the number entering the studies, which may differ from the number analysed.

Parties are categorised as healthcare practitioners, participants/patients, and carers (including peers and significant others). Tripartite contracts involve patients, carers and healthcare practitioners.