Relations of cotinine and carbon monoxide to self-reported smoking in a cohort of smokers and ex-smokers followed over 5 years
Bibliographic record
Abstract
We describe the persistence of discrepancies between biochemical measures of smoking and self-reported smoking status in a cohort of clinical trial participants across 5 years. The Lung Health Study, a randomized trial in 10 clinical centers in North America, enrolled 3923 participants in smoking intervention and 1964 in usual care in 1987 and 1988. Smoking status was assessed at baseline and at five annual follow-up visits by self-report, salivary cotinine and expired-air carbon monoxide. Compared to self-report, sensitivity and specificity of cotinine and carbon monoxide were similar across 5 years. Evidence of error in self-reports of quitting smoking persisted across 5 years, although it declined over time. Multivariate models confirmed that self-report bias was characteristic of the early years in the study. Significant covariates differed between cotinine and carbon monoxide models. When cotinine was used for verification, about half of the individuals in the smoking intervention group with self-report bias at the first year continued to exhibit bias for 5 years. In absolute terms, the errors associated with measurement were small, but they persisted over 5 years. Some differences appeared to be related to the distinction that carbon monoxide verification was immediate, while cotinine verification was deferred.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".