2) BMI was calculated from self-reported height and weight and may be influenced by ethnic differences in reporting.
For example, the impact of reporting guidelines could be measured by examining their level of uptake (eg, how frequently they are 'used' by researchers or editors) or by assessing any differences in reporting completeness between papers that do and do not use reporting guidelines.
We do not believe that our findings can be fully explained by differences in diagnoses, reporting practices or increases in risk factors where information was lacking.
Information biases may have resulted from the sensitivity of the questions, differences in reporting by gender and the reporting of partners' drinking by respondents rather than the partners themselves.
Due to the small numbers of x rays reported on by some of the radiologists, we identified the two radiologists reporting on the majority of x rays and grouped the rest together; we then assessed differences in reporting style by comparing each of the high reporters with the "rest".
It said: "Due to differences in reporting by our sources, in some cases our new displacement figures reflect the total number of people displaced during the year, whereas in others they reflect only the number of people that remained in displacement at the year's end".
Differences in reporting by state could also affect geographic patterns (4 ).
Although researchers attempt to account for differences in reporting by combining reports, this may inevitably be a biased pursuit based on individual factors.
In addition, the observed variations may have been further amplified by inaccuracies of diagnoses and differences in reporting chronic hypertension, which may predate pregnancy (chronic, prevalent hypertension), or occur for the first time during pregnancy and persist thereafter (chronic, incident hypertension).
A recent meta-analysis of the accuracy of self-reports of cancer screening concluded that national survey data overestimate the prevalence of screening and mask disparities by race and ethnicity because of differences in reporting accuracy [ 23].
