Validation of the Migraine-Specific Quality of Life Questionnaire version 2.1 (MSQ v. 2.1) for patients undergoing prophylactic migraine treatment

OBJECTIVE: Health-related quality of life (HRQoL) is an important outcome measure of migraine treatments. Although a number of migraine-specific HRQoL questionnaires exist, their measurement characteristics have only been examined for patients undergoing acute treatment of migraine. The goal of the current study was to evaluate measurement properties of the widely used Migraine-Specific Quality of Life Questionnaire version 2.1 (MSQ v. 2.1) within a group of patients undergoing prophylactic migraine treatment. METHODS: Various measurement properties of the MSQ were examined in a sample of 916 migraineurs undergoing prophylactic treatment who had scores at baseline and follow-up, as well as baseline SF-36. First, we used confirmatory factor analysis (CFA) and differential item functioning (DIF) to assure the accuracy and stability across groups of the MSQ scoring for all three subscales (Role Restrictive, Role Preventive, and Emotional Functioning). Next, item- and scale-level properties were examined, such as item-total correlations, internal consistency, and convergent and discriminant validity. RESULTS: Initial findings revealed that item 12 (measuring frustration on the Emotional Functioning subscale) performed poorly. Subsequent to its removal, the 13-item MSQ displayed excellent measurement properties, including stable latent structure at baseline and endpoint, no gender or age biases on items, appropriate item-level and scale-level reliabilities, and markedly higher convergent validity compared to discriminant validity. CONCLUSION: The 13-item MSQ appears to be an appropriate measure of migraine-specific HRQoL for patients undergoing migraine prophylaxis. Moreover, given the stability of the latent structure over time, the interpretation of scores is likely to remain quite consistent throughout a clinical trial.     

The psychometric properties of the Migraine-Specific Quality of Life Questionnaire version 2.1 (MSQ) in chronic migraine patients

Objective

The Migraine-Specific Quality of Life Questionnaire version 2.1 (MSQ) has been shown to have good psychometric performance in measuring headache impact in migraine patients, but its properties specifically in chronic migraine (CM) patients are unknown. The objective of this study was to evaluate the psychometric properties of the MSQ in a group of CM patients undergoing prophylactic treatment.

Methods

Measurement properties of the MSQ were examined using two international, multicenter, randomized clinical trials evaluating onabotulinumtoxinA as headache prophylaxis in CM patients (N = 1,376). Confirmatory factor analysis (CFA) was used to test the latent structure of the MSQ in CM patients. The reliability, convergent and discriminant validity, and responsiveness of the MSQ were assessed.

Results

CFA confirmed the currently proposed three-factor MSQ latent structure across the two studies. Good reliability was observed for all three MSQ scales, across studies and time points. MSQ scale scores strongly correlated with the scores of the Headache Impact Test-6 (HIT-6). Analysis of known-groups validity indicated that MSQ scale scores discriminated between groups of patients differing in their 28-day headache frequency were as follows <10, 10–14, and ≥15 days, and the sample-derived quartiles of the total cumulative hours of headache were as follows <140, 140 to <280, 280 to <420, and ≥420 h (p < 0.0001), across both studies and time points. MSQ change scores were higher in magnitude in groups experiencing greater decline in headache frequency (p < 0.001).

Conclusion

The MSQ is a psychometrically valid tool that can be used to reliably measure the impact of migraine among CM patients.     

Acromegaly Quality of Life Questionnaire (AcroQoL)

Acromegaly is a chronic disease with an important impact on patients, Health Related Quality of Life (HRQoL). The ability to effectively measure Health Related Quality of Life is central to describing the impacts of disease or treatment upon the patient, therefore the importance of having a disease specific questionnaire for acromegaly. For the development of the AcroQoL questionnaire different sources of information were used: first a literature search was performed to identify relevant papers describing the impact of acromegaly in HRQoL, second the main domains of impact on HRQoL were identified by 10 experts endocrinologists, and third ten in-depth semi-structured interviews were conducted in acromegalic patients to identify domains and items related to the self-perceived impact of acromegaly in patients' life. After a proper qualitative analysis a preliminary 38 item questionnaire was obtained. Rasch analysis concluded with a final 22 item questionnaire. The measurement properties (validity and reliability) of the resulting final questionnaire were tested and compared using standard procedures (Cronbach's Alpha and item-total correlation). The evaluation of the item parameters confirmed the construct validity of the new instrument. Responsiveness to change was assessed in a small sample of 32 acromegalic patients with active disease in Spain who were administered the AcroQoL and the generic questionnaire EuroQoL 5-D. The results showed a statistically significant relationship between all the dimensions of AcroQoL and the VAS (visual analogic scale) of EQ-5D. An improvement in the global score of AcroQoL was related to a global improvement in the VAS of the EQ-5D.     

Psychometric Development of the Individualized Retinopathy-Dependent Quality of Life Questionnaire (RetDQoL)

Objectives:  Psychometric development of the Retinopathy-Dependent Quality of Life (RetDQoL) questionnaire in a cross-sectional study of 207 German patients with diabetic retinopathy. Forty patients (19%) also had clinically significant macular edema.
Methods:  Principal component analyses identified factor structure, and Cronbach's alpha assessed internal consistencies. Construct validity was examined by testing the additional impact of macular edema and expected relationships of RetDQoL scores with visual impairment, stage of diabetic retinopathy, subscales of the SF-12, and scores of the Retinopathy Treatment Satisfaction Questionnaire (RetTSQ). Analyses were conducted using the RetDQoL's AWI score (average weighted impact of diabetic retinopathy on 26 life domains) and its two overview items (present QoL in general and retinopathy-specific QoL). Content validity was investigated using an open-ended question to identify any additional items needed.
Results:  A forced one-factor solution of the 26 specific weighted impact ratings showed all items except working life (applicable to 27%) to load >0.55, and Cronbach's alpha was 0.96, showing very high reliability. Greater impairment, worse diabetic retinopathy, and macular edema were associated with greater negative impact on scores. AWI correlated as expected more highly with retinopathy-specific QoL ( r  = 0.71, P  < 0.01) than with present QoL ( r  = 0.28, P  < 0.01). RetDQoL scores correlated moderately with SF-12 subscales ( r  = 0.22–0.51, P  < 0.01) and RetTSQ scores ( r  = 0.27–0.51, P  < 0.01). For six domains, >60% of patients reported no impact. No additional domains were needed.
Conclusions:  The RetDQoL is valid and reliable for patients with diabetic retinopathy with or without macular edema. It may be shortened if findings are confirmed cross-culturally.     

Validity and Reliability of the Italian Version of the Quality of Life,Enjoyment and Satisfaction Questionnaire

The Quality of Life, Enjoyment and Satisfaction Questionnaire (Q-LES-Q) is increasingly used in psychiatry because it gives emphasis to the subjective perspective of patients on physical, psychological and social domains. This paper reports on the validation of the Italian version of the Q-LES-Q in a large multicenter study (EQUIP) conducted at five Italian sites on outpatients in treatment for anxiety disorders. Study participants underwent a broad assessment of psychopathology including the MINI-International Neuropsychiatric Interview, the Symptom Checklist (SCL-90) and the Clinical Global Impression (CGI). Cronbach’s alpha was used to determine the internal consistency of the Q-LES-Q areas and Pearson’s r was used to analyze the correlation between the areas of Q-LES-Q and those of the other instruments. The internal consistency of the Q-LES-Q proved to be substantial (>0.80 in each of the areas) as well as the test–retest reliability. The convergent validity of the Q-LES-Q vs. the Work and Social Adjustment Scale was examined. High correlations were found between scales measuring similar constructs in the two instruments and lower correlation between scales measuring different constructs. In conclusion, the Italian version of the Q-LES-Q proved to be as valid and reliable as the original English version.     

Psychometric performance of the Asthma Quality of Life Questionnaire in a US sample

The purpose of this study was to examine the psychometric characteristics of the Juniper Asthma Quality of Life Questionnaire (AQLQ) in a sample of asthmatics from the USA, employing data from the Asthma Symptom Utility Index (ASUI) validation study. One hundred and sixty-one adults (66 men) undergoing standard care in an asthma clinic participated in the study (mean age=34.7±10.7 years, mean duration of illness=17.3±11.22 years and mean FEV1% predicted=85.6%±17.1%). The internal consistency reliability (?) ranged from 0.90 (environment subscale) to 0.95 (overall score) and the 2 week reproducibility (ICC) ranged from 0.81 (activities subscale) to 0.93 (symptoms subscale). The AQLQ was significantly correlated with an asthma disease severity scale and the Health Utilities Index (p < 0.001). No relationship was found between the AQLQ score and FEV1% predicted. Men reported better overall quality of life (QoL), fewer activity limitations and less environmental exposure than women (p < 0.01), while patients with a high school education or less had more severe asthma and poorer QoL across all subscales (p < 0.001). This may reflect the differential experiences of asthma across gender and socioeconomic groups. The results suggest that the AQLQ may be a useful outcome measure for clinical trials conducted in the USA.     

The value of adding the Quality of Life Enjoyment and Satisfaction Questionnaire to outcome assessments of psychiatric inpatients with mood and affective disorders

Purpose  In the domain of mental health outcomes, increasing interest has been shown in complementing traditional symptom measures with measures of a patient’s quality of life. The objective of this study was to evaluate the value of including the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) in the routine assessment battery used at a psychiatric hospital. Methods  The sample consisted of 1,276 consecutive inpatients treated at a private psychiatric hospital over a two-year period. Admission and discharge data were collected for the Q-LES-Q, the mental health subscales of the Medical Outcomes Short Form Questionnaire (SF-36), the Depression Anxiety Stress Scales, and the Health of the Nation Outcome Scale. Results  Large patient improvements from admission to discharge were seen across all instruments (effect sizes from 0.8 to 1.5), including the Q-LES-Q (effect size 1.3). The Q-LES-Q correlated with existing symptom measures, and regression analyses revealed that quality of life predicted length of hospital stay even after symptoms of depression and anxiety were taken into account. Conclusions  Although the Q-LES-Q was correlated with symptom measures already in use, it added to the ability to predict patient length of stay, and showed some divergence from measures of clinical outcomes. This pattern was seen despite intentionally restricting the sample to patients with mood and affective disorder diagnoses. The value of considering quality of life in a comprehensive assessment of mental health outcomes is discussed.     

Psychometric Assessment of the Multidimensional Quality of Life Questionnaire for Persons with HIV/AIDS (MQOL-HIV) in a Sample of HIV-Infected Women

Since the late 1980s, several HIV-specific quality of life instruments have been developed; however, little testing has been done in terms of their validity and reliability for HIV-infected women. The purpose of this study was to test the content validity, concurrent validity, internal consistency, and test-retest reliability of the Multidimensional Quality of Life Questionnaire for Persons with HIV/AIDS (MQOL-HIV) in a sample of 85 HIV-infected women. The MQOL-HIV is a 40-item scale comprised of 10 dimensions. Most of the items and all of the domains were determined content valid but revision of some of the items and domains is recommended. Concurrent validity was measured between the MQOL-HIV and the MOS-HIV and ranged from 0.51-0.81 between similar domains. Of the 10 domains and the entire instrument, 7 had a Cronbach's alpha over 0.70 (range 0.43-0.92). Eight domains and the entire instrument achieved test-retest correlation coefficients over 0.70 (range 0.60-0.96). Although some revision may make the scale more content-valid for HIV-infected women, given due care in the interpretation of results, the MQOL-HIV can be used with female populations in its current form.     

Most of the Quality of Life in Essential Tremor Questionnaire (QUEST) psychometric properties resulted in satisfactory values

ObjectiveThis study sought to assess the psychometric attributes of the Quality of Life in Essential Tremor Questionnaire (QUEST) by undertaking an independent validation.Study Design and SettingThis was an observational, multicenter, cross-sectional study carried out in Neurology Departments of general hospitals. The following assessments were applied: Louis Rating Scale, Clinical Assessment of Tremor, Clinical Global Impression of Severity (CGI-ET), Hospital Anxiety and Depression Scale (HADS), EQ-5D, and QUEST (Spanish version).ResultsOne hundred and eighteen consecutive patients were included. According to the CGI-ET, most of patients had mild (42.4%) or moderate (43.2%) impact of tremor on performing daily activities. Fully computable QUEST data were 60.2%. The QUEST Summary Index (QUEST-SI) displayed marginal floor or ceiling effect. On the whole, QUEST internal consistency and reproducibility were satisfactory (Cronbach's alpha values: 0.73–0.86; QUEST-SI intraclass correlation coefficient: 0.77). Factor analysis identified eight factors (73.6% of the variance) that could be grouped into six, relatively coincident with the questionnaire's dimensions. The QUEST-SI correlated moderately with the EQ-5D index (r_S = ?0.40), HADS—Depression (r_S = 0.39), and CGI-ET (r_S = 0.39), and strongly with the QUEST scale for self-evaluation of tremor severity (r_S = 0.63). The standard error of measurement was 8.00.ConclusionApart from a substantial problem of acceptability, most of the tested psychometric attributes of the QUEST resulted satisfactory.     

Concordance between supervised and postal administration of the Mini Asthma Quality of Life Questionnaire (MiniAQLQ) and Asthma Control Questionnaire (ACQ) was very high

BACKGROUND AND OBJECTIVE: There is increasing international interest in using patient-based outcome measures to evaluate interventions. We compared responses to postal administration of Mini Asthma Quality of Life Questionnaire (MiniAQLQ) and Asthma Control Questionnaire (ACQ) with the gold standard of supervised self-completion. STUDY DESIGN AND SETTING: Validation study involving 96 adults, recruited from U.K. general practice, sent the postal questionnaires with an instruction sheet 1 week before supervised self-completion. Responses for those whose quality of life (n=56) or asthma control (n=61) had 'not changed' between postal and supervised completions were compared using paired-sample t-tests, Pearson's correlation coefficient (r), and intraclass correlation coefficient (ICC). RESULTS: For the MiniAQLQ, overall mean scores were similar in both groups: Postal=5.14 (SD=1.42) vs. Supervised=5.17 (SD=1.39), with mean difference of -0.03 (95% CI=-0.14, 0.08; P=.59), with a high degree of correlation (r=.96, P<.001) and concordance (ICC=0.96; 95% CI=0.93, 0.98; P<.001). For the ACQ, overall mean scores (with SD) were also similar in both groups: Postal=1.24 (SD=1.09) vs. Supervised=1.26 (SD=1.10), with mean difference of -0.02 (95% CI=-0.12, 0.08; P=.74), with good correlation (r=.94, P<.01) and concordance (ICC=0.94; 95% CI=0.90, 0.96; P<.01). CONCLUSIONS: Correlation and concordance between supervised and postal administration of the MiniAQLQ and ACQ are very high. Users may confidently choose the mode of administration most appropriate to their needs.     

Validating the theoretical structure of the Treatment Self-Regulation Questionnaire (TSRQ) across three different health behaviors

Nearly 40% of mortality in the United States is linked to social and behavioral factors such as smoking, diet and sedentary lifestyle. Autonomous self-regulation of health-related behaviors is thus an important aspect of human behavior to assess. In 1997, the Behavior Change Consortium (BCC) was formed. Within the BCC, seven health behaviors, 18 theoretical models, five intervention settings and 26 mediating variables were studied across diverse populations. One of the measures included across settings and health behaviors was the Treatment Self-Regulation Questionnaire (TSRQ). The purpose of the present study was to examine the validity of the TSRQ across settings and health behaviors (tobacco, diet and exercise). The TSRQ is composed of subscales assessing different forms of motivation: amotivation, external, introjection, identification and integration. Data were obtained from four different sites and a total of 2731 participants completed the TSRQ. Invariance analyses support the validity of the TSRQ across all four sites and all three health behaviors. Overall, the internal consistency of each subscale was acceptable (most alpha values >0.73). The present study provides further evidence of the validity of the TSRQ and its usefulness as an assessment tool across various settings and for different health behaviors.     

Development and preliminary validation of the food intolerance Quality of Life Questionnaire (FIQLQ): Adult Form

Quality of Life Research - Approximately 20% of children and adults avoid certain foods because of perceived food intolerance. Valid and reliable health-related quality of life instruments are...     

Testing the EORTC Quality of Life Questionnaire on cancer patients with heterogeneous diagnoses

This study aimed to contribute to the validation of the 30-item Quality of Life Questionnaire developed by the European Organization for Research and Treatment of Cancer Study Group (EORTC QLQ-C30). The sample consisted of 177 cancer patients with heterogeneous diagnoses. A series of scales representing various dimensions of quality of life were tested, including those proposed by the EORTC Study Group. Mokken's non-parametric latent trait model for unidimensional scaling was used as the basic scaling procedure. This model gives coefficients of scalability in addition to reliability coefficients. In terms of scalability measured by Loevinger's H, all EORTC Study Group scales, except the cognitive functioning scale were found to be quite satisfactory. The cognitive functioning scale and the role functioning scale were below the satisfactory level in terms of reliability (internal consistency). In total, our study strengthens the external validity of the EORTC QLQ-C30 and confirms that it may be used on cancer patients with various diagnoses.This study is supported by grants no 89090/001-002 from the Norwegian Cancer Society and by the Faculty of Medicine, University of Trondheim. The study has been evaluated and approved by the Regional Ethical Committee for Medical Research.     

Reliability and validity of the Infant and Toddler Quality of Life Questionnaire (ITQOL) in a general population and respiratory disease sample

OBJECTIVE: To evaluate feasibility, internal consistency, test-retest reliability, and concurrent and discriminative validity of the Infant and Toddler Quality of Life Questionnaire (ITQOL) for parents of pre-school children with 12 scales (103-items) covering physical and psychosocial domains and impact of child health on parents, in comparison with the TNO-AZL Pre-school Children Quality of Life Questionnaire (TAPQOL). METHODS: Parents of children from a random general population sample (2 months-4 years old; n = 500) and of an outpatient clinic sample of children with respiratory disease (5 months-[Formula: see text] years old; n = 217) were mailed ITQOL and TAPQOL questionnaires; a retest was sent after two weeks. RESULTS: Feasibility: The response was >or=80% with few missing and non-unique ITQOL-answers (<2%) in both study populations. Some ITQOL-scales (3-4 scales) showed a ceiling effect (>25% at maximum score). Internal consistency: All Cronbach's alpha >0.70. Test-retest Intraclass Correlation Coefficients (ICCs) were moderate or adequate (>or=0.50; p < 0.01) for 10 ITQOL-scales. Validity: ITQOL-scales, with a few exceptions, correlated better with predefined parallel TAPQOL scales than with non-parallel scales. Five to eight ITQOL-scales discriminated clearly between children with few and with many parent-reported chronic conditions, between children with and without doctor-diagnosed respiratory disease and with a low and a high parent-reported medical consumption (p < 0.05). CONCLUSIONS: This study supported the evidence that the ITQOL is a feasible instrument with adequate psychometric properties. The study provided reference ITQOL scores for gender/age subgroups. We recommend repeated evaluations of the ITQOL in varied populations, especially among very young children, including repeated assessments of test-retest characteristics and evaluations of responsiveness to change. We recommend developing and evaluating a shortened ITQOL version.     

Responsiveness,longitudinal- and cross-sectional construct validity of the Pediatric Asthma Quality of Life Questionnaire (PAQLQ) in Dutch children with asthma

Objective: Health-related quality of life is an important measure in evaluations of the management of childhood asthma. In this study, we assessed psychometric properties, responsiveness, and longitudinal and cross-sectional construct validity of the Dutch version of the 23-item Pediatric Asthma Quality of Life Questionnaire (PAQLQ). Methods: The study group consisted of 238 6–18-year olds with asthma, with complete respiratory symptom diaries in the course of one winter season; each child had one (or more) PAQLQ measurement(s) concerning one (or more) week(s) with relatively many symptoms (n=238). Each child also had one PAQLQ measurement concerning another week with relatively few symptoms (n=238). The PAQLQ scores of the 238 children for a week with few symptoms (the symptom diary scores remained below a predefined level everyday) were compared with their PAQLQ scores for another week with many symptoms (on day 1 of that week, symptom diary scores had been above the predefined level). Additionally, in a subgroup of the study group that had experienced two or more `weeks with many symptoms' (n=101), we compared the PAQLQ-scores for two different weeks with many symptoms of these children. Results: Only the domain Emotions showed a ceiling effect (> 25% had the maximum score). All Cronbach's α's of the PAQLQ total score and domains were >0.70, except for Activities (α=0.54). Mean PAQLQ-scores were significantly different (p<0.01; n=238) between one week with few symptoms and another week with many symptoms. Contrary, in the subgroup of children with PAQLQ-measurements regarding more than one week with many symptoms (n=101), mean PAQLQ-scores did not differ significantly (p≥ 0.05) between 1week with many symptoms and another week with many symptoms. These results indicate responsiveness. (Changes in) lower respiratory tract symptoms, indicative of asthma severity, correlated better with (changes in) PAQLQ scores than (changes in) upper respiratory tract␣symptoms, which supports the longitudinal and cross-sectional construct validity. Conclusion: The assessed properties of the PAQLQ linguistic validation into Dutch were similar to those originally established for the PAQLQ in Canada. This study showed that the Dutch PAQLQ has adequate psychometric properties, excellent responsiveness, and that the longitudinal and cross-sectional construct validity is supported.     

Feasibility and Psychometric Properties of the Infant Toddler Quality of Life (ITQOL) Questionnaire in a Community-Based Sample of Healthy Infants in China

Objective Evaluate the feasibility and psychometric properties of the Infant Toddler Quality of Life (ITQOL) questionnaire as a measure of health-related quality of life (HRQOL) in a sample of Chinese infants. Methods The linguistically validated Simplified Chinese version of the ITQOL was used in a multicenter, observational study of healthy, term infants (N?=?427), age 6 weeks at enrollment, in China. At Days 1 and 48, parents/guardians completed the ITQOL, the Short Form Health Survey (SF-12v2) and the Infant Gastrointestinal Symptom Questionnaire (IGSQ). ITQOL feasibility, reliability, ceiling/floor effects, concurrent validity and discriminatory validity were evaluated. Results Feasibility of administering the ITQOL was supported by strong response rates (>?97%) with <?1% missing items for all scales except physical abilities. Reliability was acceptable (Cronbach’s alpha?>?0.70) for all scales except Day 1 General Health (0.67). Floor effects were minimal (<?2%), except Day 1 physical abilities (7%). Ceiling effects increased from Days 1 to 48 across all scales. Concurrent validity was demonstrated by correlations between ITQOL infant-focused scales and IGSQ score (r?=??0.20 to ??0.34, p?<?0.001) and between parent-focused scales and SF-12v2 mental health composite (MCS) scores (r?=?0.29–0.46, p?<?0.001). ITQOL scales discriminated between infant subgroups based on illness-related outcomes (sick visits, adverse events) and between parent subgroups based on SF-12v2 MCS scores. Conclusion The Simplified Chinese version of the ITQOL performed well in a community-based sample of Chinese infants, with evidence supporting the instrument’s feasibility, reliability, and validity. These data support the ITQOL as a valuable tool to assess HRQOL in Chinese infants.     

Responsiveness of the Acne-Specific Quality of Life Questionnaire (Acne-QoL) to treatment for acne vulgaris in placebo-controlled clinical trials

The Acne-Specific Quality of Life Questionnaire (Acne-QoL) was developed to measure the impact of facial acne across four dimensions of patient quality of life. The main objective of the current study was to evaluate the responsiveness of this instrument. Secondarily, this study provided an opportunity to extend the developer's psychometric validation. The Acne-QoL was utilized in two randomized, double-blind, placebo-controlled studies of the efficacy of Estrostep^® (norethindrone acetate/ethinyl estradiol) in the treatment of facial acne; a total of 296 Estrostep^® and 295 placebo patients were evaluated. The Acne-QoL was completed at the beginning, middle (cycle 3), and end (cycle 6) of the 6-month treatment period. The responsiveness of the Acne-QoL was demonstrated through its ability to detect both small (baseline to mid-study) and moderate (baseline to study end) treatment advantages for Estrostep^® patients. Confirmatory factor analysis supported the subscale structure, and internal consistency estimates were excellent. Convergent and discriminant validity were supported by correlations between Acne-QoL scores and clinical measures that were both in the direction and relative magnitude hypothesized. Finally, item response theory analyses confirmed that each item is highly related to its subscale's latent construct and that each subscale is sensitive across a broad range of the underlying continuum. The results of this evaluation confirm that the Acne-QoL is responsive, internally consistent, and valid.     

Mapping the Minnesota Living with Heart Failure Questionnaire (MLHFQ) onto the Assessment of Quality of Life 8D (AQoL-8D) utility scores

Quality of Life Research - The Minnesota Living with Heart Failure Questionnaire (MLHFQ) is a widely used condition-specific measure of quality of life (QoL) in patients with heart failure. To use...     

The Spanish version of the Paediatric Asthma Quality of Life Questionnaire (PAQLQ): Metric characteristics and equivalence with the original version

The Paediatric Asthma Quality of Life Questionnaire (PAQLQ), developed by Juniper etal., assesses the impact of asthma on children's daily life. It contains 23 items, covering three dimensions: symptoms, activities limitation and emotional function. Aims: To develop an equivalent Spanish version of the PAQLQ, and to assess its measurement characteristics. Methods: The forward and back-translation method was used for the adaptation. A longitudinal study (assessments at the 1st and 5th weeks), with patients from the emergency and outpatient departments of three Spanish hospitals, was designed to test the properties of the new adapted version. At each visit, a trained interviewer administered the PAQLQ, a Global Index of Change and a General Health Perception scale. The Peak Expiratory Flow Rate (PEFR) was also recorded daily, together with symptoms, during the prior week. Results: Ninety-nine patients (66.7% males, 42.4% suffering an exacerbation, mean age of 11.3years) with the following types of asthma were evaluated: mild intermittent (31.3%), mild persistent (36.4%), moderate persistent (29.3%) and severe persistent (3%). At the 1st visit, the mean pre-bronchodilator %PEFR was 87.3%. The Cronbach's ranged from 0.86 to 0.95. As expected, correlations between the PAQLQ scores, and the Asthma Control Score (0.53–0.67), the General Health Perception (0.34–0.55), and the %PEFR (0.44–0.55) were moderate. The PAQLQ scores remained unchanged in stable patients while increased significantly in those showing improvements. Conclusions: After a standard cross-cultural adaptation process, the Spanish version of the PAQLQ has shown to be equivalent to the original, with similar internal consistency reliability, validity and sensitivity to clinical changes.