Reason 7: Part of the dataset was suppressed
In the examples I mentioned yesterday (Reason 6: The entire dataset was not considered) I talked about research which does not get published simply because the incentive to publish it is not high enough. This happens frequently but unfortunately, sometimes more sinister factors are at play. Some pharmaceutical companies have been accused of deliberately suppressing findings which suggest that their drugs do not work. This phenomena is well known and there has been a lot of action in recent years to ensure that the results of clinical trials are more accessible. In some countries, anyone conducting a clinical trial is compelled to register it on a clinical trial registry. This means that anyone wanting to review the evidence will be able to find the results — including those which gave results which contradict drug company claims.
Next — Reason 8: Their belief was not based on scientific data