Table 1.

Criteria for Evaluating Genetic Association Studies

Elements	Comment
SNP Discovery and Genotyping (Completeness)	SNP discovery and genotyping of a gene should be complete (based on current literature AND re-sequencing of the gene in a subgroup of the population studied).
Haplotype Analysis	Haplotype analyses should be reported.
Population Size	Size should be large enough to have reasonable power to avoid both false negative and false positive results
Matching Cases and Controls	Appropriate matching is always a consideration
Population Stratification	Population stratification should always be addressed (in some manner)
Phenotype Definition	The best genetic association studies employ a robust definition of the phenotype (i.e. a physician's diagnosis of asthma is much less robust than one based on physiologic and clinical criteria)
Multiple Testing (Comparisons) Inter-Related Phenotypes	Issue of multiple testing must always be addressed, while acknowledging that some phenotypes are inter-related (and not independent), and Bonferroni correction may be too conservative
Replication and Role of Functional Studies	Replication is necessary unless it cannot be reasonably performed. In some cases, functional studies substitute for replication