Letters Section Editor: Robert M. Golub, MD, Senior Editor.
To the Editor: Population-based information about incidence of nonmelanoma skin cancers is important because these data are generally not collected in US registries, but methodological features of the study by Dr Christenson and colleagues1 limit the interpretation of the results and their comparability with other cancer incidence data.
The first problem is the choice of standard population. Age standardization is a commonly accepted method to nullify the age structure of particular populations and change the cancer incidence rates into indices that are compatible across different populations. The choice of standard population does not matter as long as it is accepted by all parties involved. The current standard in the United States is the US 2000 standard population that is used by the federal agencies2- 4 and, generally, by the research community. It is not specific to race. Because the authors selected the population structure of US whites in 2000 as their standard population, their rates are not comparable with other conventionally age-adjusted cancer incidence rates in this country. It is also not clear why the authors adjusted the rates in Table 1 and Table 4 of the article for sex, since standardization by sex is generally not practiced in the United States. The age- and sex-adjusted rates presented in this report may be misleading and are of limited utility for comparative studies.
Nasseri K. Basal Cell and Squamous Cell Carcinoma in Persons Younger Than 40 Years. JAMA. 2006;295(3):278-281. doi:10.1001/jama.295.3.279-a