It is important that studies using survey methodology minimise or at least recognise the influence of non-responders, as this can undermine study validity and thus generalisability to a wider population.
Tobacco firms spent years undermining studies that linked smoking to lung cancer and other diseases, and negotiators disqualified the companies from joining treaty talks based on admissions that they covered up evidence.
In Mandel's essay, she tells the story of her "heroic mother" driving away a home intruder with a gun and uses it to undermine official studies.
The first time I e-mailed Martha Lenio, a thirty-four-year-old Canadian engineer who serves as commander, she mentioned in her reply, forty minutes later, that they wished they could get more feedback, even though it might undermine the study: "It's a bit frustrating because we're highly competitive and want to be the best crew".
Doh worries that if the ministry does not quickly lift the suspension, it could undermine the study as trial participants might not receive their monthly supply of pills, as well as counseling and condoms.
There were many potential methodological biases that could undermine this study.
We judged that attempting to measure objectively episode severity at the time of oral corticosteroid initiation would undermine the study objective.
Finally, the majority of the patients in this cohort were Caucasian MSM, hence the findings cannot be generalised to a cohort that is diverse in both ethnicity and sexual orientation; however this does not undermine the study validity.
These possibilities were each considered unlikely to undermine the study findings, as the purposive sampling strategy did not result in removal of any of the ten most frequently accessed sites from the final sample, while the content analysis of the first webpage was considered highly likely to encompass the content that women actually read.
But that theory was undermined by studies showing that opiate blockers did not dampen the good mood of the physically active.
