A Cochrane review [Abstract] 1 included 20 studies with a total of 9 262 subjects. E.g., measurement of exhaled carbon monoxide (CO), lung function, or genetic susceptibility to lung cancer were used as feedback on the biomedical or potential future effects of smoking.
There was no evidence of increased cessation rates from feedback on risk exposure (consisting mainly of feedback on CO measurement) or on smoking-related disease risk (including four studies testing feedback on genetic markers for cancer risk). Feedback on smoking-related harm, including nine studies testing spirometry with or without feedback on lung age and two studies on feedback on carotid ultrasound, also did not show a benefit (RR 1.26, 95% CI 0.99 to 1.61; I2 = 34%; n = 3314). One good quality study (n=561) in primary care detected a significant benefit of lung age feedback after spirometry (RR 2.12, 95% CI 1.24 to 3.62).
| Outcome Smoking cessation at longest follow-up over 6 months | Relative effect (95% CI) | Risk with control | Risk with biomedical risk assessment (95% CI) | №of participants (studies) |
|---|---|---|---|---|
| Feedback on smoking exposure | RR 1.00 (0.83 to 1.21) | 153 per 1000 | 153 per 1000 (127 to 185) | 2368 (5) |
| Feedback on smoking-related risk | RR 0.80 (0.63 to 1.01) | 130 per 1000 | 104 per 1000 (82 to 131) | 2064 (5) |
| Feedback on smoking-related harm | RR 1.26 (0.99 to 1.61) | 117 per 1000 | 147 per 1000 (116 to 188) | 3314 (11) |
Another Cochrane review [Abstract] 2 included 81 studies. Biomedical risk feedback did not increase the likelihood of smoking abstinence at 6months (RR 1.07, 95% CI 0.81 to 1.41; I² = 40%; 7 studies, n=3491).
Comment: The quality of evidence was downgraded by study quality (inadequate or unclear allocation concealment) and by imprecision (potential for both benefit and harm).
Primary/Secondary Keywords