The use of "trend" statements in platelet-rich plasma literature

Clinicians often rely on significant results to inform clinical decisions, with the p value being a common tool to identify statistically significant data. Using trend statements to describe nonstatistically significant results can lead readers to draw misleading conclusions.

To investigate the frequency and context of trend statements in relation to non-significant findings in platelet-rich plasma (PRP) literature.

Original research articles examining the use of PRP to treat osteoarthritis or tendinopathy, published between January 2014 and December 2024, were searched on PubMed. Instances where nonstatistically significant results were labeled as a "trend" or included "trend-related statements" were examined to evaluate their use and context within the articles.

A total of 418 articles were analyzed. Trend statements were found in 65 articles (15.6%) to describe nonsignificant data. Among these, 43 articles (66.2%) reported an associated p value, and 22 (33.8%) did not. Forty-seven (72.3%) of the trend statements made were supportive of PRP. Additionally, 40 articles (61.5%) used trend statements for multiple findings, whereas 25 (38.5%) referred to a single finding. The presence or absence of a p value significantly predicted whether a trend statement was made (p < .05). There was no statistically significant difference in average journal impact factors between articles that did or did not contain trend statements, as both groups had an average impact factor of 2.3.

Trend statements are frequently used to characterize nonstatistically significant findings in the PRP literature, which may lead readers to draw incorrect statistical conclusions. Many trend statements were employed to describe multiple findings, often without an associated p value or with a p > .2.