Annals of Internal Medicine has a disturbing article from a sample of US sample of 522 American Statistical Association members.
The 4 most frequently reported inappropriate requests … by at least 20% of the respondents were …
* removing or altering some data records to better support the research hypothesis
* interpreting the statistical findings on the basis of expectation, not actual results
* not reporting the presence of key missing data that might bias the results
* and ignoring violations of assumptions that would change results from positive to negative.