During the process of translating the English version of IKHOAM into Hausa, the meanings of all items were retained in the back translation of the reconciled Hausa version and all the patients involved in the cognitive debriefing interview reported no difficulty in clarity of the language and ease of understanding of all the items. This is probably because there was no cross-cultural adaptation per se, although we followed the guidelines for cross-cultural adaptation by Beaton et al . IKHOAM was only translated into another language within the same cultural context. This observation supports the fact that IKHOAM is a Nigerian culture and environment-friendly clinical instrument.
The female to male ratios of 3:1 supports the fact that in hospital based studies, knee/hip OA is more common in Nigerian females than males [11, 12, 2] and could be a reflection of what obtains in the overall population of OA patients of moderate female bias . The fact that majority (61.2%) of all the patients with Knee/Hip Osteoarthritis in the study was aged 50 years and above with mean age of 55.7 ± 13.4 years supports the fact that OA may be regarded as a disease of middle and old age.
The scores obtained on the Hausa version correlated significantly with those on the English version. It implies that the Hausa version measures the same construct as the English version. The correlation coefficient of 0.67 between the Hausa and English versions found in this study falls within acceptable values (0.60 – 0.80) for construct validity . The absence of data on the pain duration of the participants in this study is a limitation of this study as the chronicity of their pain could not be ascertained. The significant correlation between IKHOAM scores on the Hausa version and pain intensity scores (r = -0.24) provides the evidence that the Hausa version demonstrates initial criterion for divergent validity. It is not surprising that this correlation coefficient is low, since the IKHOAM and the VAS measure dissimilar constructs. Values of correlation coefficient between dissimilar constructs usually fall between 0.20 and 0.60 . The results of this study support that of Dawson et al (2005). In that study, divergent construct validity was supported by the correlation (r = 0.34) between pain severity and physical function. Several studies comparing dissimilar constructs also fell within this acceptable range [14, 15]. The results on divergent validity of Hausa IKHOAM with the use of VAS in this study is a limitation of the study since IKHOAM is multidimensional while VAS has only one item that assesses pain. However, further studies should be carried out to further demonstrate evidence of divergent validity by comparing IKHOAM with measures of different construct e.g. Health Assessment Questionnaire (HAQ), Sickness Impact Profile (SIP).
The Cronbach's alpha values between the different parts (parts 1 and 2; parts 1 and 3; parts 2 and 3; parts 1 & 2 together and part 3) on the Hausa version of IKHOAM indicate that the Hausa version is internally consistent though there is a weak correlation between parts 1 and 2. The Cronbach's alpha of the three parts of the Hausa version ranged between 0.28 and 0.95. These values are comparable to the values got in several studies on validity of different versions of some outcome measures [6, 13, 16, 15]. The significant correlation between the patient's measured part (parts 1 & 2) and the clinician measured part (part 3) on the Hausa version of IKHOAM indicates that changes in functional ability of patients following intervention can be assessed by either the patient's self report or the clinician measure. This is similar to the findings of previous studies on the original (English) version  and the Yoruba version  that the versions of IKHOAM possess adequate criteria for internal consistency. However, we observed that the correlation between part I (Disability attributes) and part 2 (participation restriction attributes) was lower (α = 0.28) than Cronbach's alpha between other parts of the tool. This may be explained by the fact that many female participants in this study were in purdah, a common cultural/religious practice in the Northern part of Nigeria. Women in purdah have limited social life because they are compelled to stay at home most of the time.