Reliability and validity of the Turkish version of short form 36 (SF-36) in patients with rheumatoid arthritis

Abstract

Aim: Investigating reliability and validity of the Turkish version of short form-36 (SF-36) in patients with rheumatoid arthritis

Methods: Demographic data of the patients with rheumatoid arthritis were recorded. Health Assessment Questionnaire (HAQ) and Short Form 36 (SF-36) were filled out. Disease activities were computed using Disease Activity Score 28 (DAS-28). Patients were recalled after three months and were asked to state how they felt compared to their first visit, and the same tests were repeated. 

Results: 141 patients were admitted (9.9% male, 90.1% female). In the reliability study of SF-36, the Cronbach alpha value of the subscales varied in the range 0.792-0.992, hence SF-36 was found to be highly reliable. The item total score correlations were computed for each subscale and were found to be in the ranges: 0.436-0.840 for physical functioning, 0.887-0.895 for role function (physical), 0.861-0.958 for pain, 0.564-0.892 for general health perception, 0.702-0.841 for vitality (energy/fatigue), 0.949-0.952 for social functioning, 0.396-0.473 for role function (emotional) and 0.456-0.824 for mental health. The SF-36 scores from two consecutive visits spaced 3 months apart were compared and the p values were found to be greater than 0.05. The validity study was conducted for the 63 patients whose reported conditions did not change between two visits. The test-retest relation was evaluated using intra-class correlation coefficients, which ranged from 0.51 to 0.78 and the correlations of the two tests were found to be statistically significant. The comparison of SF-36 scores from two consecutive visits, all with p>0.05, showed no statistically significant changes.  

Conclusions: The Turkish version of SF-36 was found to be reliable and valid in patients with rheumatoid arthritis.

Keywords

• Reliability,Validity,Rheumatoid arthritis,SF-36

Romatoid artritli hastalarda Türkçe kısa form 36’nın (SF-36) güvenilirlik ve geçerliliği

Öz

Amaç: Romatoid artritte Türkçe SF-36’nın güvenilirlik ve geçerliliğini araştırmak.

Yöntemler: Çalışmaya alınan Romatoid artritli hastaların demografik özellikleri kayıt edildi. Sağlık değerlendirme anketi (HAQ) ve SF-36 formları dolduruldu. Hastalık aktiviteleri DAS-28 kullanılarak hesaplandı. Hastalar 3 ay sonra tekrar çağırılarak kendilerini ilk gelişlerine göre nasıl hissettikleri soruldu ve ilk gelişlerinde yapılan testler tekrarlandı.

Bulgular: Çalışmadaki 141 hastanın  %9,9’u erkek; %90,1’i kadındır. SF-36’nın güvenilirlik çalışmasında ölçek alt boyutlarının Cronbach alfa değerleri 0,792-0,992 arasında değişmekte olup, bunun sonucunda SF-36 yüksek düzeyde güvenilir bulunmuştur. Madde-toplam puan korelasyon katsayıları da her bir alt ölçek için ayrı ayrı hesaplanmıştır. Fiziksel fonksiyonda 0,436-0,840, fiziksel rol güçlüğünde 0,887-0,895; ağrıda 0,861-0,958, sağlığın genel olarak algılanmasında 0,564-0,892; vitalite (enerji)’de 0,702-0,841; sosyal fonksiyonda 0,949-0,952; emosyonel rol kısıtlamasında 0,396-0,473 ve mental sağlıkta 0,456-0,824 arasında bulunmuştur. Daha sonra her iki SF-36 ölçümü karşılaştırılmış ve p>0,05 olduğu için ikinci ölçümlerde ilk ölçümlere göre bir farklılık saptanmamıştır.

SF 36 geçerlilik çalışması, beyana dayalı durumları ikinci gelişlerinde ilkine göre değişmeyen 63 olgu üzerinde yapılmış olup; test tekrar test arasındaki korelasyon, intra-class korelasyon katsayıları ile değerlendirildiğinde her iki uygulama arasında istatistiksel olarak anlamlı ilişki görülmektedir.  Bu çalışmada korelasyon katsayıları 0,51 ile 0,78 arasında değişmektedir. SF-36 puanlarının ilk ve ikinci ölçümleri arasında istatistiksel olarak anlamlı farklılık görülmemektedir  (p>0,05).

Sonuç: Sonuç olarak Türkçe SF-36 Romatoid artritli hastalarda güvenilir ve geçerli bulunmuştur.

Anahtar Kelimeler

• Güvenilirlik,Geçerlilik,Romatoid artrit,SF-36

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