A longitudinal assessment of posttraumatic stress symptoms and pain catastrophizing after injury.

Only 63 people were analysed, and the authors themselves call this a small sample, so the effect sizes should be read as a signal, not a firm number. A quarter of the people recruited were lost by 90 days. Those who dropped out at 30 days had higher baseline catastrophizing scores (20.90 vs 12.87), which suggests the people doing worst were least likely to be followed up. Few participants actually had clinically significant catastrophizing (15% at 90 days), so it is unclear how these results apply to patients whose pain thinking is already a serious problem. The stress and catastrophizing measures are self-report questionnaires given at a single point, and the pre-injury stress questions were asked after the crash, so recall and reporting bias can distort them. This is a secondary analysis of a trial designed for different questions, and it tests associations rather than whether treating stress symptoms changes pain outcomes. Almost the whole sample was either White or non-Hispanic Black, and the authors say the results may not generalize to other groups. Pre-injury chronic pain was not excluded or formally assessed, so some participants may already have had long-standing pain problems.

No funding or conflict of interest statement appears in the supplied text. The authors state that the design was preregistered (NCT03247179) and that they were unable to share the data for ethical reasons because no data sharing plan was filed when the project was approved in 2017.

Do not read the lower pain catastrophizing scores in the app group as evidence the PTSD Coach app reduces catastrophizing. That difference did not reach significance (p = 0.064), the app comparison was not what this analysis set out to test, and the study as a whole shows that stress symptoms and catastrophic thinking go together rather than that treating one fixes the other.