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Only for dye, not for straighteners, and only for "Nonprofessional application of semipermanent dye to others", and black women. If you count up the specific cl

Only for dye, not for straighteners, and only for "Nonprofessional application of semipermanent dye to others", and black women. If you count up the specific claims made in the article, a majority are not actually supported by the study. And unless the study was preregistered for the cohorts they analyzed, the statistical analysis is suspect even at the 95% level which I still contend is too low.

gus_massa 7y ago
It's interesting to see the supplementary tables (that are free). In the supplementary table 1, classified by menopausal status, they report 55 results. The intervals that exclude 1.00 are: 1.30 (1.04, 1.62) 1.35 (1.08, 1.69) 1.41 (1.10, 1.79) 1.26 (1.02, 1.55) 1.51 (1.17, 1.94) 0.68 (0.47, 0.99) (Some are very correlated.) Anyway, they get 6 interesting results, slightly more than the expected number of false positive cases with a 95% CI interval with 55 cases. Moreover, in the last case, 1.00 is excluded because the interval is too low, i.e. in this study in the premenopausal women that applied hair dye to other person between 1 and 3 times a year got less cancer that the women that didn't. This is probably just noise, but note that this case is not highlighted in the abstract in spite they highlight a few cases where the 95% interval includes 1.00. In the supplementary table 2, classified by estrogen reception, they report also 55 results. The intervals that exclude 1.00 are: 0.78 (0.63, 0.97) 0.82 (0.70,0.95) Both are below 1.00, and neither is highlighted in the abstract. This number is close to the expected number of false positive cases with a 95% CI interval with 55 cases. I guess there is another table in the paper where they classify the women black or white, and perhaps even more classifications. So the evidence looks weak and close to the noise level.
- Knufen 7y ago
  Always remember, all articles are accessible through the Hub of Science Edit: Forgot e

gus_massa 7y ago

It's interesting to see the supplementary tables (that are free). In the supplementary table 1, classified by menopausal status, they report 55 results. The intervals that exclude 1.00 are: 1.30 (1.04, 1.62) 1.35 (1.08, 1.69) 1.41 (1.10, 1.79) 1.26 (1.02, 1.55) 1.51 (1.17, 1.94) 0.68 (0.47, 0.99) (Some are very correlated.) Anyway, they get 6 interesting results, slightly more than the expected number of false positive cases with a 95% CI interval with 55 cases. Moreover, in the last case, 1.00 is excluded because the interval is too low, i.e. in this study in the premenopausal women that applied hair dye to other person between 1 and 3 times a year got less cancer that the women that didn't. This is probably just noise, but note that this case is not highlighted in the abstract in spite they highlight a few cases where the 95% interval includes 1.00. In the supplementary table 2, classified by estrogen reception, they report also 55 results. The intervals that exclude 1.00 are: 0.78 (0.63, 0.97) 0.82 (0.70,0.95) Both are below 1.00, and neither is highlighted in the abstract. This number is close to the expected number of false positive cases with a 95% CI interval with 55 cases. I guess there is another table in the paper where they classify the women black or white, and perhaps even more classifications. So the evidence looks weak and close to the noise level.

Knufen 7y ago
Always remember, all articles are accessible through the Hub of Science Edit: Forgot e