Although a majority of trials have shown some benefit from zinc, many of them have been criticized for failing to "mask" the treatment, meaning the participants most likely knew they were using zinc, which may have skewed the results.
This suggests some asymmetry of the goodness of fit testing: whereas increased sample size minimizes incorrect power law fitting of a multi-exponential process at sample sizes of n = 640 (Figures 3,6,7), power law data could still be incorrectly fitted with multi-exponential functions in a majority of trials due to the larger number of free parameters (Table 1).
A majority of trials was of high or unclear risk of bias, indicating poor methodological quality.
Nurses or both nurses and therapists, that is, psychotherapists or psychologists, delivered the intervention in a majority of trials (n=8).
Of the 269 studies meeting the search criteria, 76 (28%) are being conducted in the US whereas a majority of trials are occurring outside the US (Table 1).
Western Europe is host to 43 studies (16%); other countries each had fewer trails but collectively accounted for a majority of trials.
Overall, we found more robust mentalizing effects (evoked and oscillatory theta activity) in the post-naming interval, suggesting that on a majority of trials, participants engaged in enhanced episodic retrieval and, most importantly, mentalizing in response to a perceived violation.
However, we found more robust mentalizing effects in the post-naming than in the pre-naming interval, suggesting that on a majority of trials, participants engaged in mentalizing only in response to a perceived violation.
Additionally, "precedent match" filler trials (and a number of other catch trials) were added as well to each test phase to ensure that participants would not learn to expect a precedent mismatch on a majority of trials (see Fig. 1, Panel A, right, bottom panel; see also Materials for detailed information).
