The Revised Fibromyalgia Impact Questionnaire (FIQR): Validation and Psychometric Properties
The Revised Fibromyalgia Impact Questionnaire (FIQR): Validation and Psychometric Properties
Introduction The Fibromyalgia Impact Questionnaire (FIQ) is a commonly used instrument in the evaluation of fibromyalgia (FM) patients. Over the last 18 years, since the publication of the original FIQ, several deficiencies have become apparent and the cumbersome scoring algorithm has been a barrier to widespread clinical use. The aim of this paper is to describe and validate a revised version of the FIQ: the FIQR.
Methods The FIQR was developed in response to known deficiencies of the FIQ with the help of a patient focus group. The FIQR has the same 3 domains as the FIQ (that is, function, overall impact and symptoms). It differs from the FIQ in having modified function questions and the inclusion of questions on memory, tenderness, balance and environmental sensitivity. All questions are graded on a 0–10 numeric scale. The FIQR was administered online and the results were compared to the same patient's online responses to the 36-Item Short Form Health Survey (SF-36) and the original FIQ.
Results The FIQR was completed online by 202 FM patients, 51 rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) patients (31 RA and 20 SLE), 11 patients with major depressive disorder (MDD) and 213 healthy controls (HC). The mean total FIQR score was 56.6 ± 19.9 compared to a total FIQ score of 60.6 ± 17.8 (P < 0.03). The total scores of the FIQR and FIQ were closely correlated (r = 0.88, P < 0.001). Each of the 3 domains of the FIQR correlated well with the 3 related FIQ domains (r = 0.69 to 0.88, P < 0.01). The FIQR showed good correlation with comparable domains in the SF-36, with a multiple regression analysis showing that the three FIQR domain scores predicted the 8 SF-36 subscale scores. The FIQR had good discriminant ability between FM and the 3 other groups; total FIQR scores were HC (12.1 ± 11.6), RA/SLE (28.6 ± 21.2) and MDD (17.3 ± 11.8). The patient completion time was 1.3 minutes; scoring took about 1 minute.
Conclusions The FIQR is an updated version of the FIQ that has good psychometric properties, can be completed in less than 2 minutes and is easy to score. It has scoring characteristics comparable to the original FIQ, making it possible to compare past FIQ results with future FIQR results.
The Fibromyalgia Impact Questionnaire (FIQ) was developed in the late 1980s and was first published in 1991, with minor revisions in 1997 and 2002. It has subsequently become one of the most frequently used tools in the evaluation of fibromyalgia (FM) patients, being cited in over 300 articles and translated into 14 languages. Over the 18 years since its publication, problems in regard to some aspects of its content and rather cumbersome scoring algorithm have become apparent. The original questionnaire used a visual analog scale (VAS) that required patients to slash a 100-mm line and was scored with a ruler. The scoring was further complicated by the need to reverse scores in one question and the use of constants to convert the first 13 questions to a standardized scale of 0 to 10. The functional questions in the first part of the FIQ were originally intended for women living in reasonably affluent countries and assumed the possession of a car, a vacuum cleaner, and a washing machine. Moreover, questions that now are considered relevant, such as dyscognition, tenderness, balance, and environmental sensitivity, were not part of the original FIQ. With these issues in mind, we have developed an online and paper-equivalent version of the questionnaire: the Revised Fibromyalgia Impact Questionnaire (FIQR) (Additional data file 1). The FIQR attempts to address the limitations of the FIQ while retaining the essential properties of the original instrument.
Abstract and Introduction
Abstract
Introduction The Fibromyalgia Impact Questionnaire (FIQ) is a commonly used instrument in the evaluation of fibromyalgia (FM) patients. Over the last 18 years, since the publication of the original FIQ, several deficiencies have become apparent and the cumbersome scoring algorithm has been a barrier to widespread clinical use. The aim of this paper is to describe and validate a revised version of the FIQ: the FIQR.
Methods The FIQR was developed in response to known deficiencies of the FIQ with the help of a patient focus group. The FIQR has the same 3 domains as the FIQ (that is, function, overall impact and symptoms). It differs from the FIQ in having modified function questions and the inclusion of questions on memory, tenderness, balance and environmental sensitivity. All questions are graded on a 0–10 numeric scale. The FIQR was administered online and the results were compared to the same patient's online responses to the 36-Item Short Form Health Survey (SF-36) and the original FIQ.
Results The FIQR was completed online by 202 FM patients, 51 rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) patients (31 RA and 20 SLE), 11 patients with major depressive disorder (MDD) and 213 healthy controls (HC). The mean total FIQR score was 56.6 ± 19.9 compared to a total FIQ score of 60.6 ± 17.8 (P < 0.03). The total scores of the FIQR and FIQ were closely correlated (r = 0.88, P < 0.001). Each of the 3 domains of the FIQR correlated well with the 3 related FIQ domains (r = 0.69 to 0.88, P < 0.01). The FIQR showed good correlation with comparable domains in the SF-36, with a multiple regression analysis showing that the three FIQR domain scores predicted the 8 SF-36 subscale scores. The FIQR had good discriminant ability between FM and the 3 other groups; total FIQR scores were HC (12.1 ± 11.6), RA/SLE (28.6 ± 21.2) and MDD (17.3 ± 11.8). The patient completion time was 1.3 minutes; scoring took about 1 minute.
Conclusions The FIQR is an updated version of the FIQ that has good psychometric properties, can be completed in less than 2 minutes and is easy to score. It has scoring characteristics comparable to the original FIQ, making it possible to compare past FIQ results with future FIQR results.
Introduction
The Fibromyalgia Impact Questionnaire (FIQ) was developed in the late 1980s and was first published in 1991, with minor revisions in 1997 and 2002. It has subsequently become one of the most frequently used tools in the evaluation of fibromyalgia (FM) patients, being cited in over 300 articles and translated into 14 languages. Over the 18 years since its publication, problems in regard to some aspects of its content and rather cumbersome scoring algorithm have become apparent. The original questionnaire used a visual analog scale (VAS) that required patients to slash a 100-mm line and was scored with a ruler. The scoring was further complicated by the need to reverse scores in one question and the use of constants to convert the first 13 questions to a standardized scale of 0 to 10. The functional questions in the first part of the FIQ were originally intended for women living in reasonably affluent countries and assumed the possession of a car, a vacuum cleaner, and a washing machine. Moreover, questions that now are considered relevant, such as dyscognition, tenderness, balance, and environmental sensitivity, were not part of the original FIQ. With these issues in mind, we have developed an online and paper-equivalent version of the questionnaire: the Revised Fibromyalgia Impact Questionnaire (FIQR) (Additional data file 1). The FIQR attempts to address the limitations of the FIQ while retaining the essential properties of the original instrument.