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The authors declare that there are no conflicts of interest.
LDM conceptualized and conducted the research, and drafted the manuscript in preparation for publication submission. QAL and KGS assisted in the conceptualization of the research and in drafting the final manuscript. MJS assisted in the logistics of conducting the cross-cultural adaptation of the SA-PCS. All the authors read and approved the final manuscript.
Pain catastrophization has recently been recognized as a barrier to the healthy development of physical functioning among chronic pain patients. Levels of pain catastrophization in chronic pain patients are commonly measured using the Pain Catastrophizing Scale (PCS).
To cross-culturally adapt and validate the South African PCS (SA-PCS) among English-, Afrikaans- and Xhosa-speaking patients with fibromyalgia living in the Cape Metropole area, Western Cape, South Africa.
The original PCS was cross-culturally adapted in accordance with international standards to develop an English, Afrikaans and Xhosa version of the SA-PCS using a repeated measures study design. Psychometric testing included face/content validity, internal consistency (Cronbach’s alpha-α), test-retest reliability (intraclass coefficient correlations-ICC), sensitivity-to-change and cross-sectional convergent validity (by comparing the adapted SA-PCS to related constructs).
The cross-culturally adapted English, Afrikaans and Xhosa SA-PCS showed good face and content validity, excellent internal consistency (with Chronbach’s α = 0.98, 0.98 and 0.97 for the English, Afrikaans and Xhosa SA-PCS, as a whole, respectively), excellent test-retest reliability (with ICC’s of 0.90, 0.91 and 0.89 for the English, Afrikaans and Xhosa SA-PCS, respectively); as well as satisfactory sensitivity-to-change (with a minimum detectable change of 8.8, 9.0 and 9.3 for the English, Afrikaans and Xhosa SA-PCS, respectively) and cross-sectional convergent validity (when compared to pain severity as well as South African versions of the Tampa scale for Kinesiophobia and the revised Fibromyalgia Impact Questionnaire).
The SA-PCS can therefore be recommended as simple, efficient, valid and reliable tool which shows satisfactory sensitivity-to-change and cross-sectional convergent validity, for use among English, Afrikaans and Xhosa-speaking patients with fibromyalgia attending the public health sector in the Western Cape area of South Africa.