TY - JOUR
T1 - Developing an item bank to measure the coping strategies of people with hereditary retinal diseases
AU - Prem Senthil, Mallika
AU - Khadka, Jyoti
AU - De Roach, John
AU - Lamey, Tina
AU - McLaren, Terri
AU - Campbell, Isabella
AU - Fenwick, Eva
AU - Lamoureux, Ecosse
AU - Pesudovs, Konrad
PY - 2018/7/1
Y1 - 2018/7/1
N2 - Purpose: Our understanding of the coping strategies used by people with visual impairment to manage stress related to visual loss is limited. This study aims to develop a sophisticated coping instrument in the form of an item bank implemented via Computerised adaptive testing (CAT) for hereditary retinal diseases. Methods: Items on coping were extracted from qualitative interviews with patients which were supplemented by items from a literature review. A systematic multi-stage process of item refinement was carried out followed by expert panel discussion and cognitive interviews. The final coping item bank had 30 items. Rasch analysis was used to assess the psychometric properties. A CAT simulation was carried out to estimate an average number of items required to gain precise measurement of hereditary retinal disease-related coping. Results: One hundred eighty-nine participants answered the coping item bank (median age = 58 years). The coping scale demonstrated good precision and targeting. The standardised residual loadings for items revealed six items grouped together. Removal of the six items reduced the precision of the main coping scale and worsened the variance explained by the measure. Therefore, the six items were retained within the main scale. Our CAT simulation indicated that, on average, less than 10 items are required to gain a precise measurement of coping. Conclusions: This is the first study to develop a psychometrically robust coping instrument for hereditary retinal diseases. CAT simulation indicated that on an average, only four and nine items were required to gain measurement at moderate and high precision, respectively.
AB - Purpose: Our understanding of the coping strategies used by people with visual impairment to manage stress related to visual loss is limited. This study aims to develop a sophisticated coping instrument in the form of an item bank implemented via Computerised adaptive testing (CAT) for hereditary retinal diseases. Methods: Items on coping were extracted from qualitative interviews with patients which were supplemented by items from a literature review. A systematic multi-stage process of item refinement was carried out followed by expert panel discussion and cognitive interviews. The final coping item bank had 30 items. Rasch analysis was used to assess the psychometric properties. A CAT simulation was carried out to estimate an average number of items required to gain precise measurement of hereditary retinal disease-related coping. Results: One hundred eighty-nine participants answered the coping item bank (median age = 58 years). The coping scale demonstrated good precision and targeting. The standardised residual loadings for items revealed six items grouped together. Removal of the six items reduced the precision of the main coping scale and worsened the variance explained by the measure. Therefore, the six items were retained within the main scale. Our CAT simulation indicated that, on average, less than 10 items are required to gain a precise measurement of coping. Conclusions: This is the first study to develop a psychometrically robust coping instrument for hereditary retinal diseases. CAT simulation indicated that on an average, only four and nine items were required to gain measurement at moderate and high precision, respectively.
KW - Psychometric properties
KW - Rasch analysis
KW - Computerized adaptive testing
KW - Item bank
KW - Hereditary retinal diseases
KW - Coping
UR - http://purl.org/au-research/grants/NHMRC/1031838
UR - http://www.scopus.com/inward/record.url?scp=85046486371&partnerID=8YFLogxK
U2 - 10.1007/s00417-018-3998-5
DO - 10.1007/s00417-018-3998-5
M3 - Article
SN - 0721-832X
VL - 256
SP - 1291
EP - 1298
JO - Graefe's Archive For Clinical and Experimental Ophthalmology
JF - Graefe's Archive For Clinical and Experimental Ophthalmology
IS - 7
ER -