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Results for “construct validity”

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PubMed2002

Development and validation of a short measure of health status for individuals with acute myocardial infarction: the myocardial infarction dimensional assessment scale (MIDAS).

The purpose of this study was to develop and validate a disease-specific health status measure for individuals with myocardial infarction (MI). The development of the myocardial infarction dimensional assessment scale (MIDAS) followed three main stages. Stage 1 consisted of in-depth, semi-structured, exploratory interviews conducted on a sample of 31 patients to identify areas of salience and concern to patients with MI. These interviews generated 48 candidate questions. In stage 2 the 48-item questionnaire was used in a postal survey to identify appropriate rephrasing/shortening, to determine acceptability and to help identify sub-scales of the instrument addressing different dimensions of MI. Finally, in stage 3 the construct validity of MIDAS subscales was examined in relation to clinical and other health outcomes. A single centre (district general hospital) in England was used for stages 1 and 3 and a national postal survey was conducted for stage 2. A total of 410 patients were recruited for the national survey (stage 2). Full data were available on 348 (85%) patients. One hundred and fifty-five patients were recruited to test construct validity (stage 3). The MIDAS contains 35 questions measuring seven areas of health status: physical activity, insecurity, emotional reaction, dependency, diet, concerns over medication and side effects. The measure has high face, internal and construct validity and is likely to prove useful in the evaluation of treatment regimes for MI.

Activities of Daily Living↗

PubMed2007

Construction and validation of a patient- and user-friendly nursing home version of the Geriatric Depression Scale.

OBJECTIVE: To construct a patient- and user-friendly shortened version of the Geriatric Depression Scale (GDS) that is especially suitable for nursing home patients. METHODS: The study was carried out on two different data bases including 23 Dutch nursing homes. Data on the GDS (n = 410), the Mini Mental State Examination (n = 410) and a diagnostic interview (SCAN; n = 333), were collected by trained clinicians. Firstly, the items of the GDS-15 were judged on their clinical applicability by three clinical experts. Subsequently, items that were identified as unsuitable were removed using the data of the Assess project (n = 77), and internal consistency was calculated. Secondly, with respect to criterion validity (sensitivity, specitivity, area under ROC and positive and negative predictive values), the newly constructed shortened GDS was validated in the AGED data set (n = 333), using DSM-IV diagnosis for depression as measured by the SCAN as 'gold standard'. RESULTS: The eight-item GDS that resulted from stage 1 showed good internal consistency in both the Assess data set (alpha = 0.86) and the AGED dataset (alpha = 0.80). In the AGED dataset, high sensitivity rates of 96.3% for major depression and 83.0% for minor depression were found, with a specificity rate of 71.7% at a cut-off point of 2/3. CONCLUSION: The GDS-8 has good psychometric properties. Given that the GDS-8 is less burdening for the patient, more comfortable to use and less time consuming, it may be a more feasible screening test for the frail nursing home population.

Aged↗

PubMed2006

Reliability and validity of the Spanish Version of the Crisis in Family Systems-Revised.

Increasing the representation of Spanish-speaking study participants requires development and dissemination of reliable and valid translated scales. In the urrent study the construct validity was assessed of the Spanish version of the Crisis n Family Systems-Revised, a measure of contemporary life stressors, with a convenience sample of 377 parents interviewed in a study of childhood asthma, although over half of the respondents did not have children with asthma. Most respondents were foreign-born women between 20 to 60 years old (M=35, SD=7). 52% had not completed high school or its equivalent, and 55% reported a household income of dollar 15,000 or less. For a subsample of 25 respondents test-retest reliability was .86 over 2 wk. Reporting more life stressors was associated with greater depressive symptomatology, poorer physical and mental health function, and lower household income. These relationships support the construct validity of the test in Spanish. This study provided strong evidence that this version is a valid and reliable measure of life stressors for a Spanish-speaking population living in the United States.

Adult↗

PubMed2003

[A study of the nursing service perceived by consumers and providers, and the tool that measures nursing service].

PURPOSE: This study was performed to measure the nursing service perceived value by consumer and providers, and to investigate the relationship among nursing service, general satisfaction and hospital revisiting intent, and to examine the tools that measures nursing service's reliability, construct validity and usefulness. METHOD: The questionnaire was developed and distributed to 300 patients and 210 nurses at three general hospitals. For data analysis, SPSS/PC program was used. RESULT: The nursing service perceived value by providers is higher than that by consumers. There are distinctive difference in the expectation, and importance and performance values of the nursing service perceived. In examination of the relationship among nursing service, general satisfaction and hospital revisiting intent, nursing service has a deep relationship with general satisfaction, but doesn't have relationship with hospital revisiting intent. The tool that measures nursing service has a good reliability and construct validity. In analysis on the usefulness between the tools, SERVPERF tool is more useful than SERVQUAL tool. CONCLUSION: The nursing service perceived value by consumer is different that by providers, and the tool that measures nursing service has a good reliability and construct validity. The SERVPERF tool is more useful than SERVQUAL tool.

English Abstract↗

PubMed1997

Subjective symptomatology of asthma: validation of the asthma symptom checklist in an outpatient Spanish population.

The objective of this study was to validate the Asthma Symptom Checklist (ASC) so that it could be reliably used to assess the subjective symptomatology of asthma attacks in our context. Subjective symptomatology of asthma was examined in a group of 100 adult Spanish outpatients (57 women, 43 men; 17-69 years of age) with asthma. All of them completed the modified version of the ASC as well as questionnaires of depression, anxiety, and self-management of asthma (self-efficacy expectancies and health care utilization). Data about duration and severity of asthma, as well as dyspnea and %FEV1, were also recorded. The highest reliability Cronbach alpha indexes were for the panic-fear and fatigue scales. The oblique rotation of the ASC revealed five correlated factors (53% of the total variance explained): 1) panic-fear, 2) airways obstruction, 3) airways obstruction and panic-fear, 4) fatigue and irritability, 5) hyperventilation. The structure of factors was revalidated using orthogonal (varimax) rotation. Construct validity was examined by Person product-moment coefficient correlations, ANOVAs (asthma severity x ASC scores), and t-tests (sex by ASC scores). Panic-fear showed the best construct validity, as it was related to the severity of the asthma and the use of high-cost health care resources. There were no differences in ASC scores either on the basis of the asthma severity or on the sex of patients. The ASC factors represent stable components of subjective symptomatology of asthma attacks, especially with regard to the panic-fear and the hyperventilation subscales; however, the structure of the checklist as a whole was not identical to those reported in other studies. Correlations of the ASC with clinical variables related to asthma severity support the construct validity of the instrument and confirm its utility to evaluate the subjective symptomatology of asthma attacks in outpatients.

Adolescent↗

PubMedDate not supplied

The Scientific Misconduct Questionnaire--Revised (SMQ-R): validation and psychometric testing.

PURPOSE: The overall purposes of this article are to report the development of a survey instrument, Scientific Misconduct Questionnaire-Revised (SMQ-R) that elicits the perceptions of research coordinators managing clinical trials about the various aspects of scientific misconduct and to present psychometric analyses for the SMQ-R. METHODS: A panel of five researchers and research coordinators reviewed the original SMQ (Rankin and Esteeves, 1997) and suggested an additional 42 items based on the review of the literature and their own experiences in research. The SMQ-Revised (SMQ-R) consists of 68 closed-choice items in six sections and one section with 12 open-ended questions. The SMQ-R was sent to 5302 persons who were members of the Association for Clinical Research Professionals (ACRP) or subscribers to Research Practitioner, published by the Center for Clinical Research Practice (CCRP). FINDINGS: Internal consistency of subscales was assessed with Cronbach's alpha and ranged from .83 to .84. Confirmatory factor analysis was used to test construct validity of the instrument subscales. The factor structure was assessed with the principal factors method, using the squared multiple correlations as initial communality estimates followed by varimax (orthogonal) or biquartimax (oblique) rotations. Analyses revealed five distinct factors among three subscales. Construct validity for the SMQ-R was also assessed by testing hypothesized relationships using the known groups approach. CONCLUSION: The current effort demonstrated the usefulness of the SMQ-R in obtaining information from a national sample of experienced research coordinators about their perceptions of the prevalence of different types of scientific misconduct and of factors that influence the occurrence of misconduct. The psychometric evaluation of the SMQ-R suggests good internal consistency for most subscales and suggests adequate construct validity of the instrument as a whole. The analyses also suggest that further refinement of the instrument for future studies is warranted.

Attitude↗

PubMed2003

Analytic global OSCE ratings are sensitive to level of training.

PURPOSE: There are several reasons for using global ratings in addition to checklists for scoring objective structured clinical examination (OSCE) stations. However, there has been little evidence collected regarding the validity of these scales. This study assessed the construct validity of an analytic global rating with 4 component subscales: empathy, coherence, verbal and non-verbal expression. METHODS: A total of 19 Year 3 and 38 Year 4 clinical clerks were scored on content checklists and these global ratings during a 10-station OSCE. T-tests were used to assess differences between groups for overall checklist and global scores, and for each of the 4 subscales. RESULTS: The mean global rating was significantly higher for senior clerks (75.5% versus 71.3%, t55 = 2.12, P < 0.05) and there were significant differences by level of training for the coherence (t55 = 3.33, P < 0.01) and verbal communication (t55 = 2.33, P < 0.05) subscales. Interstation reliability was 0.70 for the global rating and ranged from 0.58 to 0.65 for the subscales. Checklist reliability was 0.54. CONCLUSION: In this study, a summated analytic global rating demonstrated construct validity, as did 2 of the 4 scales measuring specific traits. In addition, the analytic global rating showed substantially higher internal consistency than did the checklists, a finding consistent with that seen in previous studies cited in the literature. Global ratings are an important element of OSCE measurement and can have good psychometric properties. However, OSCE researchers should clearly describe the type of global ratings they use. Further research is needed to define the most effective global rating scales.

Canada↗

PubMed1991

Convergent and discriminant validity of FIRO-B questionnaire.

The Kramer-Froehle controversy about the construct validity of FIRO-B questionnaire was evaluated with a multitrait-multimethod design. 113 women and 26 men completed the FIRO-B questionnaire. After the examiner had given a lecture on the FIRO-dimensions, the subjects rated themselves on these dimensions. Only three out of six intercorrelations on the validity diagonal were statistically significant. Of the discriminant validity comparisons 80% met the required criterion. Our results confirmed Kramer's results about the construct validity of the FIRO-B questionnaire.

Adult↗

PubMed2006

A short form of the Diabetes Quality of Life for Youth questionnaire: exploratory and confirmatory analysis in a sample of 2,077 young people with type 1 diabetes mellitus.

AIMS/HYPOTHESIS: The aim of this study was to test the construct validity of the Diabetes Quality of Life for Youth (DQOLY) questionnaire in a large representative sample of young people with type 1 diabetes mellitus. METHODS: The 52-item DQOLY questionnaire was completed by 2,077 adolescent individuals (aged 10-18 years) with type 1 diabetes. Participants were recruited from 22 paediatric diabetes centres in 18 countries across Europe, Asia and North America. HbA(1c) levels were determined once and analysed centrally. RESULTS: Exploratory factor analysis generated three possible measurement models of a revised questionnaire, two with four factors and one with six factors with all models indicating the presence of one satisfaction scale, but with many of the impact and worry scale items either double loading or not loading on any factors. Subsequent confirmatory analysis indicated that compared with the original DQOLY scales, the six-factor solution was the best-fitting model. CONCLUSIONS/INTERPRETATION: The DQOLY factor structure does not show construct validity in a large, diverse representative sample of young people with type 1 diabetes. However, a revised (short-form) version of the DQOLY is proposed that has improved construct validity, adequate internal consistency, and more precise and hypothesised association with HbA(1c). It is anticipated that this shorter version will enhance the acceptability and clinical utility of the measure, making it more feasible to introduce as part of routine care.

Adolescent↗

PubMed1995

Patient utilities in fibromyalgia and the association with other outcome measures.

OBJECTIVE: To compare in patients with fibromyalgia (FM) utilities derived by rating scale and standard gamble methods; to gain insight into construct validity by relating utility values to other outcome measures; to assess the sensitivity to change of utilities. METHODS: A total of 73 patients with FM were randomized into one of 3 groups: low impact fitness training, biofeedback, or controls. At baseline and after 6 mo the Maastricht Utility Measurement Questionnaire was applied. By means of both the rating scale and standard gamble method patients were asked to value their own health status. Construct validity of patient utility measurements was evaluated by Spearman correlation and multiple regression of baseline values with pain, stiffness, patient's global assessment, Sickness Impact Profile (SIP), modified Health Assessment Questionnaire and Arthritis Impact Measurement Scale (AIMS). Sensitivity to change was assessed against changes in these outcomes. RESULTS: Rating scale utilities correlated significantly (p < 0.05) with patient's global assessment (rs = 0.53), pain (rs = -0.47), SIP (rs = -0.43), and with 9 of 11 dimensions of the AIMS (rs ranging from 0.23 to 0.62). Standard gamble utilities correlated significantly with mobility, pain, and arthritis impact of the AIMS scale (rs from 0.22 to 0.36) and with pain by visual analog scale (rs = -0.24) and patient's global assessment (rs = 0.32). Multiple regression analysis showed that patient's global assessment explained 41% (rating scale) and 10% (standard gamble) of total variance in baseline utilities. Also, 16% of the variance in change in rating scale utility values was explained by changes in patient's global assessment. In contrast, variance of changes in standard gamble utility values was not explained significantly by changes in other disease outcomes. CONCLUSION: Rating scale utilities correlated more strongly with disease outcome measures than standard gamble utilities. Also, construct validity for the rating scale was better than for the standard gamble. In FM, utility measurement is sensitive to the method chosen to elicit patient priorities.

Adolescent↗

PubMed2005

Development and validity testing of the neuropathy total symptom score-6: questionnaire for the study of sensory symptoms of diabetic peripheral neuropathy.

OBJECTIVE: The aim of this study was to develop and validate a neuropathy sensory symptom scale, the Neuropathy Total Symptom Score-6 (NTSS-6), which evaluates individual neuropathy sensory symptoms in patients with diabetes mellitus (DM) and diabetic peripheral neuropathy (DPN) in clinical trials, with the intent of distinguishing a response to therapy. METHODS: The NTSS-6 questionnaire was developed to evaluate the frequency and intensity of individual neuropathy sensory symptoms identified frequently by patients with DPN (ie, numbness and/or insensitivity; prickling and/or tingling sensation; burning sensation; aching pain and/or tightness; sharp, shooting, lancinating pain; and allodynia and/or hyperalgesia). The NTSS-6 was administered 8 times over a 1-year period to DPN patients. The NTSS-6's reliability (determined by internal consistency and test-retest reproducibility), construct validity, convergent validity, and minimally clinically important differences (MCIDs) were determined. RESULTS: The NTSS-6 was administered to a total of 205 patients at 10 centers in the United States, Canada, Belgium, Germany, Hungary, Croatia, Slovenia, and the United Kingdom. Internal consistency was demonstrated at all 8 visits (Cronbach's alpha > 0.7). Test-retest reproducibility (intraclass correlation coefficient >0.9) was observed during the baseline period and at end point. Construct validity was demonstrated by statistically significant correlations between the NTSS-6 total score and the Neuropathy Symptoms and Change (NSC) score (r = 0.773-0.885, P < 0.001). Convergent validity was demonstrated by statistically significant correlations between the change in NTSS-6 total scores and the following: change in NSC scores (r = 0.519-0.708, P < 0.001); change in Neuropathy Impairment Score of the Lower Limbs and composite nerve function scores (r = 0.188-0.202, P < 0.007), and categories of the Clinical Global Impressions (r = 0.402, P < 0.001). The within- and between-groups MCIDs for the total NTSS-6 total scores were -1.26 and 0.97 points, respectively. The mean (SD) within-group MCID for all patients who improved on the Clinical Global Impression was -2.29 (3.4) points. CONCLUSIONS: The NTSS-6 provided a valid assessment of neuropathy sensory symptoms in this sample of patients with DM and DPN, which suggests that it may be useful for symptom evaluation in clinical trials and practice. The NTSS-6 showed internal consistency, test-retest reliability, and construct validity. There was also convergent validity of the scores, indicating that the NTSS-6 may be a suitable questionnaire for clinical trials that evaluate symptoms of DPN in this well-defined patient population.

Adult↗

PubMed2005

[Measuring preferences for depressive health states].

OBJECTIVE: The purpose of this study was to analyse the construct validity and the concurrent validity of the EuroQol instrument (EQ-5D self-classifier, EQ VAS and EQ-5D indices), time trade-off (TTO) and contingent valuation (willingness-to-pay) for preference-based valuation of depressive health states. METHODS: A survey of a representative sample (N = 3522) of the non-institutionalised population aged 18 and above in Germany was conducted using the EQ-5D, TTO and contingent valuation as well as the SF-12 questionnaire. Construct validity was analysed by comparing 130 respondents in whom 12-month prevalence for major depression, minor depression, or dystimia according to DSM-IV was identified based on a version of the Composite International Diagnostic Interview (WMH-CIDI) to respondents without depressive disorders. Concurrent validity was analysed by assessing the correlation between these measures in the group with depressive disorders. RESULTS: In the group with depressive disorders, problems in all EuroQol dimension except for mobility were significantly more frequent, and mean values of all analysed preference measures except for willingness-to-pay were less favourable than in the group without depressive disorders (EQ VAS score 67 vs. 78; EQ-5D index [VAS] 83 vs. 94; EQ-5D index [TTO] 0.81 vs. 0.91; TTO 0.89 vs. 0.95; always p < 0.001). In the group with depressive disorders, EQ VAS score and EQ-5D indices were significantly correlated one with another (ranging from r = 0.63 to r = 0.92) as well as with the mental and the physical component scale of the SF-12 (ranging from r = 0.26 to r = 0.45) and with willingness-to-pay (ranging from r = - 0.20 to r = - 0.22); besides, willingness-to-pay was significantly correlated with TTO (r = - 0.46). CONCLUSIONS: The results of this study point to the construct validity and concurrent validity of preference measures in patients with depressive disorders.

Activities of Daily Living↗

PubMed2006

[Choosing a quality-of-life questionnaire].

UNLABELLED: Define the objective of the questionnaire: Discrimination: do you want a questionnaire to enable you to describe the quality of life of patients or to compare the quality of life between groups of patients, for example, to determine who has improved and who has gotten worse? ASSESSMENT: do you want a questionnaire to help you measure changes over time (improvement or aggravation) in your patients? Determine the properties of instruments necessary for this objective: If the objective is discrimination, analyze: construct validity, reliability. If the objective is assessment, analyze construct validity, sensitivity to changes. Choose the general category of questionnaire: generic questionnaire, specific questionnaire.

Activities of Daily Living↗

PubMed1989

Comment on Holloway and McNally's (1987) "Effects of Anxiety Sensitivity on the Response to Hyperventilation".

Holloway and McNally (1987) found that normals with high scores on the Anxiety Sensitivity Index (ASI), an instrument developed to assess beliefs regarding the adverse consequences of anxiety, reported more anxiety and more frequent and intense somatic sensations following hyperventilation than did normals with low scores on the ASI. They concluded that this result provides support for the construct validity of the ASI and thus for the construct of anxiety sensitivity. Nevertheless, we argue that (a) the developers of the ASI have conflated beliefs regarding the adverse consequences of anxiety with fear of these consequences, (b) the accumulated evidence for the construct validity of the ASI is weak, and (c) Holloway and McNally's design and analyses do not permit them to exclude the more parsimonious explanation that trait anxiety accounts for their findings. Implications for research on anxiety sensitivity are discussed.

Anxiety↗

PubMed1996

Do codependent traits involve more than basic dimensions of personality and psychopathology?

OBJECTIVE: Despite widespread use of the term codependency, empirical evidence regarding its construct validity is generally lacking. This study analyzed the construct validity of codependency as measured by Potter-Efron and Potter-Efron's Codependency Assessment Questionnaire (CAQ). It attempted to determine the CAQ's factor structure and whether there are any unique relations between symptoms of codependency and parental alcoholism after controlling for basic dimensions of personality and psychopathology. METHOD: Participants were 467 (246 male, 221 female) young adult children of alcoholics and controls who contributed complete questionnaire data at the fourth wave of a longitudinal study of factors related to alcohol use and abuse. RESULTS: The CAQ showed reliability and basically a one dimensional structure, and CAQ scores were significantly related to family history. Although much of this relation between family history and codependency was accounted for by neuroticism and symptoms of general psychopathology, a small, but significant, association between family history and codependency remained even after statistically controlling for personality and psychopathology. CONCLUSIONS: We conclude that, although there may be unique aspects of the purported codependency syndrome that are related to a family history of alcoholism, most of the relation between codependency and family history appears to be "explained" by general negative affectivity.

Adult↗

PubMed2005

Assessing alcohol misuse during pregnancy: evaluating psychometric properties of the CAGE, T-ACE and TWEAK in a Brazilian setting.

OBJECTIVE: The present article evaluates the psychometric properties of the Portuguese-language versions of the CAGE, TWEAK and T-ACE questionnaires when used to identify alcohol misuse during pregnancy and compares these to historical data from the English-language versions. Also, construct validity of the Portuguese versions of those instruments was assessed. METHOD: Data were collected from March to September 2000 in three large public maternity wards in Rio de Janeiro, Brazil. Sample size varied according to the analysis. An intra-observer reliability evaluation involved 95 replications carried out within a 24-48 hour period. Kappa was used as an estimator. Cronbach's alpha coefficient, whether or not each item from the analysis was excluded, and the item-rest point-biserial correlations addressed internal consistency (N = 786). For the appraisal of construct validity (n = 528), the relationship between alcohol misuse (evaluated by each instrument according to different cutoff points) and several putative underlying theoretically related dimensions (schooling, age, smoking, marital status, social support, illicit drug use, domestic violence and per capita household income) were evaluated. RESULTS: All kappas were above 0.70. The alpha coefficients for the Portuguese versions ranged from 0.48 to 0.68, a finding consistent with studies assessing the original instruments in English. Yet, irrespective of the instrument concerned a systematic increase was observed whenever the item on morning alcohol use ("Eye-opener") was removed from the analysis. Regarding construct validity, most tested hypotheses were corroborated, except for the CAGE using the cut-off point of 2. CONCLUSIONS: This study confirms other authors' findings that all but the aforementioned CAGE may be recommended to identify heavy alcohol use during pregnancy in general as well as in Portuguese-speaking populations in particular.

Adult↗

PubMed2006

The validity of the repeatable battery of neuropsychological status in acute stroke.

The construct validity of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was investigated in a sample of 210 acute ischemic stroke patients seen on an inpatient rehabilitation unit. Intercorrelations between the six index scores were found to be relatively consistent with previously published work. A principal components analysis yielded a two-factor (Language/Verbal Memory and Visuospatial/Visual Memory) solution that accounted for 61% of the variance. Correlations generated between the resulting factor scores, the Controlled Oral Word Association Test (COWA), the Visual Form Discrimination Test (VFD), Boston Diagnostic Aphasia Examination (BDAE) Complex Ideational Material Test (CIM), the presence of neglect as determined by Line Bisection Test performance, and the Mini Mental Status Examination (MMSE) supported the validity of these factors. A comparison of the obtained factor scores in a subgroup of 111 left and right hemispheric stroke patients showed that the left hemispheric stroke patients performed more poorly on the Language/Verbal Memory factor score than did right hemispheric stroke patients while the converse was true for the Visuospatial/Visual Memory factor score. Implications for the construct validity of the RBANS and its use and interpretation in clinical assessment are discussed.

Aged↗

PubMed2001

Assessment of a disease-specific muscular impairment rating scale in myotonic dystrophy.

OBJECTIVE: To document the intra/interrater reliability and the construct validity of the Muscular Impairment Rating Scale (MIRS) in assessing patients with myotonic dystrophy type 1 (DM1). The MIRS is a ordinal five-point rating scale, established in accordance with the clinically recognized distal to proximal progression of the muscular involvement in DM1, based partly on a manual muscle testing (MMT) of 11 muscle groups. METHODS: To assess the reliability of the MIRS, 55 patients with DM1 were examined by three different observers, one of them evaluating each patient twice. Intra- and interobserver reliability of the MIRS was measured using Cohen's weighted kappa. To assess the construct validity of the MIRS, correlations were made with the Functional Status Index (FSI) and eight timed functional tasks. RESULTS: The intraobserver reliability of the MIRS was excellent (weighted kappa = 0.84), and the interobserver reliability was interpreted as a substantial agreement (weighted kappa = 0.77 to 0.79). The correlation coefficients between MMT scores and MIRS grades were all highly significant (r(s) = -0.81 to -0.88, p < 0.001). The FSI showed a significant progressive increase of the total median dependence score in activities of daily living from 0 in MIRS grade 1 to 39 in MIRS grade 5 (p < 0.001). The time needed to perform the eight functional tasks was also found to significantly increase in relation with the progression of the MIRS grades. CONCLUSION: The MIRS is a quick, simple, and reliable measurement of muscular impairment in DM1. The FSI questionnaire and the timed motor activities supported its construct validity. The MIRS is useful to monitor major stages of DM1 progression, to study the natural history of the disease, and to identify homogeneous groups of patients for clinical trials.

Adolescent↗