Patient self-assessed measures of comfort and function, such as the Simple Shoulder Test (SST) and the American Shoulder and Elbow Surgeons (ASES) score, obtained before and after surgery provide the essential measure of the value of the procedure to the patient.
The authors of this paper suggest that the Patient-Reported Outcomes Measurement Information System (PROMIS) Upper Extremity CAT (UE-CAT) may be an acceptable alternative to the ASES.
They assessed responses from 107 patients prior to their having rotator cuff repair. They did not assess the postoperative responses.
PROMIS UE-CAT correlated to a degree with the ASES (r=0.684) and had a 4% floor effect and no ceiling effect. The ASES had no floor or ceiling effects. PROMIS UE-CAT person-item maps revealed excellent test item coverage between floor and ceiling effects; however, all PROMIS UE-CAT items except “Difficulty putting on a jacket” demonstrated non-sequentially ordered responses indicating poor reliability of item responses corresponding to shoulder function. While PROMIS UE-CAT initially required fewer test items for overall equivalent coverage of shoulder function assessment, final models after recursive item elimination revealed the ASES instrument to have more well-fitting items over a broader range of shoulder function.
The authors concluded that: "Until further refinements in the PROMIS UE-CAT instrument are made, it should not replace the ASES instrument in patients undergoing primary RCR."
Comment: The rationale for computer adaptive tests (CAT) is that they can "tailor question delivery, decrease time to completion, and increase compliance".
However, by definition, computer adaptive testing requires that the patient have access to and is trained in the use of a computer interface that they will use before surgery and after surgery at the designed followup intervals. While this may be straightforward for some patients, other patients may not have the necessary computer training and access. The result is the risk of non-response bias - patients not completing the requisite PROMIS sessions may be - for example, older, less educated, less healthy, and less well-off - than those who have PROMIS training and access.
For example in a study discussed in this link, one third of the eligible patients did not provide a 12-month PROMIS response. Even though the preoperative characteristics of the responders and non-responders were similar, there is no way to know if the outcomes of the missing 1/3 were similar to those of the responders. It appears that the characteristics of the PROMIS system has the potential for excluding a substantial number of patients - possibly those with inferior results or those from less advantaged socio-economic situations (see this link).
For contrast compare the response rate from the above study with that in What is a Successful Outcome Following Reverse Total Shoulder Arthroplasty?, a study in which the more easily accessible Simple Shoulder Test enabled 87% of the patients in the original sample to provide two year followup. In contrast to the PROMIS, the SST or the ASES form can be completed anywhere and requires only a pencil or a pen.
Another article is relevant:Correlation of PROMIS Physical Function Upper Extremity Computer Adaptive Test with American Shoulder and Elbow Surgeons shoulder assessment form and Simple Shoulder Test in patients with shoulder arthritis
The purpose of this study was to evaluate the Patient-Reported Outcomes Measurement Informative System Physical Function Upper Extremity Computer Adaptive Test (PROMIS PFUE CAT) measurement tool against the already validated American Shoulder and Elbow Surgeons (ASES) shoulder assessment form and the Simple Shoulder Test (SST) in patients with shoulder arthritis.
The average times to complete the SST and PROMIS PFUE CAT were determined to be 96.9 ± 25.1 seconds and 62.6 ± 22.8 seconds, respectively. The question is whether the saving of 34 seconds is worth the limitations of the PROMIS?
The scatter plot from this article also brings up another issue with the PROMIS: four patients who indicated that they could perform none of the 12 functions of the SST, still had PROMIS scores in the same range as three patients what could perform eight of these functions. Thus, the PROMIS was unable to discriminate between a non-functioning shoulder and a reasonably functional one.
The goal of patient self-assessment is to capture the largest percentage of those potentially eligible, without the risk of non-response bias that may systematically exclude certain categories of patients. Computer adaptive testing may not be the ideal tool in this regard.
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Here are some videos that are of shoulder interest
