SF 36 and Health Status

Last updated: Tuesday, January 25 2005

Shoulder conditions do not exist in isolation. They affect the overall health status of the individual and conversely are affected by the individual's overall health. A practical method for documenting health status is the SF 36 self-assessment questionnaire. It contains standardized questions that are then reduced to eight health status scores.

This particular questionnaire is in broad usage throughout medicine; thus it offers the opportunity to compare the association of deficits in health status of patients with shoulder conditions to those with other musculoskeletal and other medical conditions.

We obtain SF 36 data on all patients presenting to the University of Washington Shoulder and Elbow Service.

These parameters are affected differently by different shoulder diagnoses as is seen in the comparison chart (see figure 1).

Each of these scores changes to a degree with advancing age. Data from a relatively general cross section of the population were reported by Radosevich et al (Radosevich DM Wetzler H Wilson SM: Health status questionnaire (HSQ) 2.0: Scoring comparisons and reference data. Health Outcomes Institute Bloomington MN 1994). It is of note that these reference data cohorts did not exclude individuals with chronic back pain arthritis and other chronic conditions; thus these control data represent a population cross section and not the health status of "normal" individuals. The age dependency for the eight scales are shown in these graphs: physical function social function the ability to carry out the desired physical role and emotional role vitality overall bodily comfort general health and mental health (see figures 2 through 8).

The SF-36 has demonstrated validity across all ages including the elderly. For instance among 1200 randomly selected subjects completing the questionnaire patients with arthritis had the second highest bodily pain score and the second most limited physical role function score. They also had the second best emotional role function score and the best mental health score out of all the chronic conditions investigated. For social function vitality and general health perceptions individuals with arthritis scored in the middle of the group.

We have found it convenient to present SF 36 data in terms of the percent of patients who are more than one standard deviation below the mean for their age. Figure 9 shows sample data for patients presenting to us with degenerative joint disease. The standardized nature of the SF 36 self-assessment questionnaire facilitates comparisons among diagnoses for example degenerative and rheumatoid joint disease of the shoulder (see figure 10). This test also permits comparison of the health status before and after treatment for example in patients having total shoulder arthroplasty for degenerative glenohumeral joint disease (see figure 11).

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Figure 1
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Figure 9
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Figure 10
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Figure 11
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Figure 12