I've been trying to use the POSAS score for evaluation of burn scar reconstruction. However, I find the Patient's part difficult to use. The patients all seem to become a bit embarrassed in trying to put scores on their symptoms. I'm left with the impression that they are all under-scoring their problems. This might be ok statistically, since if everything is under-scored, then trends will still be valid, but has anyone else experienced this? More to the point, has anyone overcome this problem???
You are not alone in raising this aspect of Self Reported Outcomes by Patients.
Their biases in under-reporting may seem evident , yet IPD analysis becomes important as some may overreport. Whether the association of denial or pleasing the assessor or other confounding factors limit the validity and reliability is debatable.
You may find this link useful from Queensland
Burns. 2012 Feb;38(1):6-18. doi: 10.1016/j.burns.2011.09.021. Epub 2011 Nov 1.
A systematic review of the quality of burn scar rating scales for clinical and research use.
Tyack Z1, Simons M, Spinks A, Wasiak J.
I would suggest direct contact with the first author who may more than willing to help you overcome this problem or have suggestions of how to best minimize this or to handle it in a clinical meaningful manner (not merely statistically significant) Author information
http://www.ncbi.nlm.nih.gov/pubmed/22047828
Many thanks indeed Professor Kaell. That's a useful ref. I'll contact the Queensland team.
We have established a follow up questionnaire for our patients that considers POSAS for scaring scores. My feeling is the scale is not easy to use. I have had to train my own staff to uniformly score these patients and it usually takes some time. As for patients they do have a bias towards underscoring however after 12 months of using the scale (about 80 patients) the global results seem to be useful and patients are pleased to know that they can report there own progress. We follow up at 3-6-12 months and will publish our results promptly.
We did a study comparing the professional's score to the patient's score and in about 70% they had exactly the same score (on 3 characteristics that could be compared). You might find the publication useful (Hoogewerf et al 2014).
Many thanks indeed for your comments Dr Kaell, Dr Van Loey, Dr Arriagada and Dr Acosta-Batista. Your points made me think - Should the patient make their score away from the observer? If the patient and observer are both present at the same time, then that's good, since the scores are recorded at the same time, temperature, lighting etc... However, it might be bad, if the patient perceives an element of pressure from the presence of the scoring observer, to score their scar low. Does anyone insist on both observer and patient scoring together, or do you keep them apart?