- This is a large retrospective case-control study with well-specified participants.
- In general, the conclusions are backed up by the data; however, no data was collected on brand name or ingredients of hair products. Not having this data likely impacts the results and conclusions of this research. For example, the chemical make-up of certain hair products used by White women may be different than AA women.
- The association between use of relaxers and straighteners in White women and increased breast cancer risk should be interpreted with caution due to small sample.
- There are likely different reasons women use hair products at different stages of life. For example, women may be more likely to use hair dyes later in life to cover grey hair. This study did not take into account different patterns of use of certain hair products generally (i.e. older age when using hair dye), or between AA and White women specifically (i.e. regular relaxer use versus no relaxer use).
- This study should not be considered as proof of an effect of use of certain hair products on breast cancer risk but rather a potential association which needs further study.