Limitations include small number of detected cases, self-report bias and recall bias; both at screening and at the diagnostic interview, self-reported figures of weight and height might have been biased due to the potential delicate nature of these measures among individuals with eating problems.
Furthermore, while informant reports are helpful in supporting the diagnosis, the moderately high correlations with self-report suggest that in most cases self-report alone should be sufficient.
In 78.3% of the cases, self-reports corresponded with the EMR data.
In some cases, self-reports from the BRFSS were highly reliable but prevalence rates differed from other surveys.
At each site, most women approached were enrolled in the study; cases self-reported a diagnosis of breast cancer at any time, and controls reported no diagnosis of any cancer.
An additional limitation is the use of only one reporter (in this case self-report) of depressive symptoms and alcohol use, which could hence result in reporter bias.
One diagnosed pre-gestational diabetes case (self-report) was excluded.
† adjusted for reporting status (all cases vs self reported cases only), age at diagnosis (<48,48-65,>65), tradiation(radiation, chemo, surgery - yes/no), education (<12, 12, >12), marital status (yes/no), total calories (continuous), pack years (median = 18.5), and age at first alcoholic drink (<18,18-20,>20).
In ten (50%) of these cases the self reported number and dosage of medication on the DAMS corresponded with medication records.
In 4 of these last 5 cases, self and/or parental report also suggested that the trios were dizygotic.
Studies ascertaining cases of type 2 diabetes by self report involved uncertainty in ascertainment, and thus numbers of cases were revised by a positive predictive value (proportion of verified cases among self reported cases) (see supplementary information and table S3).
