White 2013.
| Methods | Randomised controlled trial; conducted from December 2010 to March 2011 Setting: Thailand rural villages |
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| Participants | 215 smokers (10.5% of eligible smokers in 30/42 villages) Participants grouped in 2‐person teams, either choosing their own partner or being randomly assigned based on village and gender. Controls also paired up N = 128 experimental; 68 control; 13% women, mean age 51, mean CPD 13.5 |
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| Interventions | All participants received an initial group counselling session, and a further session at 3‐month follow‐up
Intervention Grp: signed a 'team commitment' contract: a) Opened a savings account, with a minimum deposit of THB 50 (USD 1.67), and a starter bonus of THB 150 (USD 5), with an extra bonus of THB 150 if the account balance reached THB 150 over the 10‐week deposit period. Community Health Workers visited weekly for the 10‐week duration, to try to elicit additional voluntary contributions b) Cash bonus of THB 1200 (USD 40) to each partner if both were abstinent at 3 months c) Weekly supportive text messages Intervention group received deposits back if verified quit at 3 months |
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| Outcomes | 7‐day PPA at 3 months, 6 months, 13 to 16 months ("14 months"); urine cotinine verified at 3 months and 6 months , but 14 months self‐report only Participants not attending at 3 months and 6 months were contacted by CHW or by phone, and tested at home if claimed abstinent Other outcomes: % receiving 3‐month bonus; %s quit as teams at 3 months, 6 months and 14 months; partner choice vs random assignment; team vs individual enhancing likelihood of quitting; impact of text messages; cost effectiveness |
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| Notes | New for 2015 update; Funded by grants from the US National Institute on Aging and the US National Institute for Child Health and Development Additional information supplied by the author |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Quote: "computer‐generated random numbers" by an independent programmer |
| Allocation concealment (selection bias) | Low risk | Quote: "...concealing the sequence from other field staff and participants" |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | Abstinence biochemically validated |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Intervention: 1/128 death, 3/128 missing baseline data; Control: 1/68 missing baseline data |