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A cross sectional assessment of health status instruments in patients with rheumatoid arthritis participating in a clinical trial. Minocycline in Rheumatoid Arthritis Trial Group.

OBJECTIVE: To (1) validate the Short-Form Health Survey (SF-36) as a generic functional health status measure in patients with rheumatoid arthritis (RA); and (2) assess correlations between the SF-36 and other outcome measures used in the Minocycline in Rheumatoid Arthritis (MIRA) Trial. METHODS: We conducted a cross sectional analysis of the final visit outcome measures from the 48 week, multicenter, placebo controlled, double blind MIRA trial. Multitrait scaling analyses assessed convergent and discriminant validity and internal consistency reliability of the SF-36 in the study patients. Responses to comparable items on the SF-36 and modified Health Assessment Questionnaire (M-HAQ) regarding physical functioning were compared and questions from both instruments were also compared to other RA outcome measures. RESULTS: In patients with RA, the SF-36 had high internal consistency and reliability, high discriminant and high convergent validity. Moderate correlations were observed (r = -0.46 to -0.61, p < 0.01 in each case) for comparable items on the SF-36 and M-HAQ regarding dressing, walking, and bending. Joint tenderness score correlations with items on the M-HAQ and SF-36, and joint tenderness score correlations with the SF-36 scales were higher than for joint swelling scores. Physician and patient global assessments were most highly correlated (r = 0.58 and 0.66; p < 0.01, respectively) with the SF-36 bodily pain item. CONCLUSION: The SF-36 is a valid instrument for this RA population. The SF-36 correlates with the M-HAQ and the physician and patient global assessments. The usefulness of the SF-36 in measuring change in RA clinical trials requires testing in longitudinal studies.

Adult↗

The IPR inventory: development and psychometric characteristics.

The purpose of this study was to develop, validate, and norm a measure of dimensions of interpersonal relationships that are salient to nursing: social support, reciprocity, and conflict. The selection of these concepts was guided by social exchange and equity theories. In the first phase of the study, 44 respondents were interviewed to provide narrative data from which to develop items so that items would be grounded in lived experience. Content validity of items was judged by a panel of 11 experts. The revised 39-item instrument was tested in successive steps with a total of 340 students, patients, and community residents for reliability and validity, including internal consistency reliability, test-retest reliability, factor analysis, and three forms of validity assessment (theory testing, contrasted groups, and multitrait-multimethod comparison). The three subscales of social support, reciprocity, and conflict demonstrated repeated internal consistency and test-retest reliability. Strong evidence of construct validity was demonstrated for the social support and the conflict subscales; validity of the reciprocity subscale was equivocal.

Adult↗

Validation and calibration of the Kabi Pharmacia International Growth Study prediction model for children with idiopathic growth hormone deficiency.

In 1999 a model was published for prediction of growth in children with idiopathic GH deficiency (IGHD) during GH therapy, derived using data from the Kabi Pharmacia International Growth Study (KIGS) database (Pharmacia \|[amp ]\| Upjohn, Inc., International Growth Database). We validated and calibrated this KIGS model for growth in the first year of GH therapy using data from 136 Dutch children with IGHD. Observed vs. predicted outcomes were plotted, and the fitted regression line was significantly different from the line of identity (P = 0.03). It appeared that the predictions were too extreme: relatively low predictions were too low, relatively high predictions were too high. This is a well known phenomenon in the context of prediction models, called overoptimism. For valid application to other data the KIGS predictions should be calibrated. Calibrated predictions are obtained using Y(cal) = Y(orig) + (2.153 - 0.192 x Y(orig)), where Y(cal) is the calibrated prediction, and Y(orig) is the KIGS prediction. The calibrated prediction will be higher than the original KIGS prediction when the original prediction is less than 11.2 cm/yr and will be lower otherwise. The variability of the prediction errors of the calibrated predictions was positively related to the value of the prediction (P < 0.001), described by the equation SD(pred err) = -1.017 + 0.286 x Y(cal). Our calibrated model will give better predictions for children with IGHD fulfilling the same criteria.

Calibration↗

Cultural and linguistic validation of questionnaires for use in international studies: the nine-item BPH-specific quality-of-life scale.

Questionnaires to evaluate symptoms and quality of life are being increasingly used in urology. It is, however, important that these questionnaires show equivalence when they are used in international, collaborative studies. Precise linguistic and cultural validation should greatly increase their compatibility in different population and cultural groups. Indeed, recent progress in the validation of symptom scores, such as the International Prostate Symptom Score (I-PSS), has helped international comparability in epidemiology and clinical trials. The management of benign prostatic hyperplasia (BPH) increasingly focuses on quality of life and the development of a successful BPH-specific quality-of-life questionnaire is an important advance in the study of BPH. The nine-item BPH-specific quality-of-life scale is currently undergoing linguistic and cultural validation and appears to be satisfactory for extensive use in different cultures.

Cultural Diversity↗

The reliability of upper limb anthropometry in older Chinese people.

OBJECTIVE: To evaluate the validity of the Durnin-Womersley equations and to derive our local predictive equations for body fat from upper limb skinfold thicknesses in older Chinese people in Hong Kong. To evaluate the validity of mid-arm circumference and corrected arm muscle area in predicting lean tissue mass in the same population. DESIGN: Comparison of fat percentages predicted by Durnin-Womersley (D-W) equations with those estimated by Dual energy X ray absorptiometry (DXA). Predictive equations derived from regression between upper limb skinfold thicknesses and fat percentages estimated by DXA were similarly evaluated in internal and external validation groups. Mid-arm circumference (MAC) and corrected arm muscle area (CAMA) were correlated with the limb lean tissue mass, body lean tissue mass and fat percentage. SUBJECTS: 354 female and 263 male, apparently well, community dwelling subjects, aged 69-82 y; of which 40 subjects of each sex were randomly selected from the study population for internal validation of the local predictive equations; 60 female and 33 male hospital medical outpatients, aged 61-87 y, were recruited for external validation. MEASUREMENTS: Triceps and biceps skinfold thicknesses, mid-arm circumference, body mass index, fat percentages, limb and whole body lean tissue masses estimated by Hologic QDR-2000 bone densitometer. RESULTS: Fat percentages calculated by D-W equations were significantly different from those estimated by DXA (average difference -2.4 (s.d. 4.8)% and +2.1 (5.2)% in females and males respectively). The corresponding differences for our local predictive equations were not significant (-0.9 (4.7)% and -0.5 (5.0)% in females and males respectively). There was a trend of under-estimation of body fat with increasing fatness. In the hospital medical outpatients, there was a significant difference between fat percentages predicted by our equation and those by DXA in female (-2.9(5.3)%), but not in male (+0.3(4.3)%) subjects. In males, MAC correlated with limb and body lean tissue masses as well as with fat percentage (r = 0.60, 0.68, 0.65 respectively). CAMA correlated similarly well with lean tissue masses but was more independent of fat percentage (r = 0.61, 0.65, 0.44 respectively). In females, both MAC and CAMA correlated poorly with limb and body lean tissue masses. Moreover, MAC correlated well with fat percentage (r = 0.80). CONCLUSION: Upper limb skinfold thicknesses measurement is a valid means of predicting body fat in older Chinese people. Local predictive equations were more reliable that D-W equations. They were, however, subject to errors at the extreme ends of body fatness and in the presence of disease. In older females, MAC and CAMA were not reliable in predicting lean tissue mass, but MAC could be used to predict fat percentages. In older males, CAMA was more reliable than MAC in predicting lean tissue mass.

Absorptiometry, Photon↗

Clinical correlates of long-term mortality after percutaneous interventions of saphenous vein grafts.

BACKGROUND: Increasing number of patients undergo percutaneous intervention of saphenous vein grafts (SVGs). However, the clinical factors associated with long-term mortality after SVG interventions are currently less known. Accordingly, the goal of present study was to evaluate clinical correlates of long-term mortality and to develop a simple bedside tool for risk stratification in patients undergoing SVG interventions. METHODS: We analyzed 1019 patients undergoing SVG interventions from the Duke Cardiovascular Disease Database (1986-2003). Cox proportional hazards model was used to identify baseline variables associated with long-term mortality, and the model variables were then used to construct a nomogram for survival probability at 4 years. RESULTS: At a median follow-up of 4 years, 24% of those undergoing SVG interventions died (interquartile range 2-7 years). Independent correlates of death at follow-up on multivariable analysis included presenting heart rate (hazard ratio [HR] 1.02, 95% CI 1.01-1.03), diabetes (HR 1.73, 95% CI 1.37-2.18), presenting heart failure (HR 1.62, 95% CI 1.27-2.06), age (per 10-year increase, HR 1.29, 95% CI 1.13-1.46), peripheral vascular disease (HR 1.59, 95% CI 1.23-2.04), renal insufficiency (HR 2.01, 95% CI 1.36-2.97), patent internal mammary graft (HR 0.67, 95% CI 0.53-0.86), body mass index < or = 25 kg/m2 (HR 0.91, 95% CI 0.85-0.97), carotid bruit (HR 1.44, 95% CI 1.12-1.85), S3 ventricular gallop (HR 1.83, 95% CI 1.11-3.03), and hypertension (HR 1.38, 95% CI 1.04-1.83) (c-index 0.83). Bootstrap validation confirmed excellent internal validity of the model (mean c-index 0.84, 95% CI 0.80-0.85). CONCLUSION: Long-term survival after SVG intervention is poor, with one fourth of patients dying at median follow-up of 4 years. The nomogram developed using the model variables provides a method for clinicians to advise patients undergoing SVG interventions regarding their long-term prognosis, thereby enhancing discharge and long-term follow-up planning and setting up of realistic expectations.

Aged↗

Development and validation of a risk score for somatic erectile dysfunction: combined results from three cross-sectional surveys.

OBJECTIVES: Some men with erectile dysfunction (ED) have difficulties discussing their condition with their physicians. Existing screening and diagnostic tools for ED often require the administration of personal questions regarding the condition. We present a simple risk score to estimate the individual likelihood of somatic ED, based on age and existing health conditions. METHODS: Data from the Cologne Male Survey (n = 4396) were used to develop a multivariable logistic regression model for the individual ED likelihood. The regression equation was both internally and externally validated using data from a national study (Berlin study) and a multinational cross-sectional study (MALES study). RESULTS: A final regression equation including age, pelvic surgery, diabetes mellitus, arterial circulatory disorder, heart disease, smoking, and hypertension reached an area under the receiver operating characteristic curve of 0.84 (0.5 means random and 1.0 perfect discrimination). Internal validation did not indicate any relevant overfit and the external validation results (national data: AUC = 0.75; multinational data: AUC = 0.67) are similar to those of other popular risk scores. CONCLUSIONS: The validated ED risk score developed from the regression equation can be used as a screening tool to identify patients who are at a high risk of somatic ED. This tool can facilitate entering into discussions between physicians and patients regarding erectile function.

Adult↗

Measurement of depression in patients with chronic obstructive pulmonary disease (COPD).

OBJECTIVE: To estimate the validity of the Hamilton Depression Scale (HDS) in a population of patients with chronic obstructive pulmonary disease (COPD). METHODS: Forty-nine patients with moderate to severe COPD were examined using the ICD-10 criteria for depression. The mean age of the patients was 71 years and 33 (64%) were women. Forty-six (94%) of the patients were also evaluated using the 17-item HDS including the six-item Hamilton Depression subscale (HDSS). Internal and external validity were measured using factor analysis, Cronbach Coefficient alpha, Loevinger coefficient of homogeneity, correlation analysis and ROC-curves. RESULTS: Twenty-three (47%) of the patients were depressed according to the ICD-10 criteria for depression. The HDSS but not the HDS showed a good internal validity. An acceptable external validity was furthermore shown for the HDSS. CONCLUSION: The HDSS can be recommended as a suitable depression rating scale for COPD patients.

Aged↗

The reliability, validity, and preliminary responsiveness of the Eye Allergy Patient Impact Questionnaire (EAPIQ).

BACKGROUND: The Eye Allergy Patient Impact Questionnaire (EAPIQ) was developed based on a pilot study conducted in the US and focus groups with eye allergy sufferers in Europe. The purpose of this study was to present the results of the psychometric validation of the EAPIQ. METHODS: One hundred forty six patients from two allergy clinics completed the EAPIQ twice over a two-week period during the fall and winter allergy seasons, along with concurrent measures of health status, work productivity, and utility. Construct validity, reliability (internal consistency and test-retest), concurrent, known-group, and clinical validities, and responsiveness of the EAPIQ were assessed. Known-group validity was assessed by comparing EAPIQ scale scores between patients grouped according to their self-rating of ocular allergy severity (no symptoms, very mild, mild, moderate, severe, very severe). Clinical validity was assessed by assessing differences in EAPIQ scores between groups of patients rated by their clinician as non-symptomatic, mild, moderate, and severe. RESULTS AND DISCUSSION: Results from the validation study suggested the deletion of 14 of 43 items (including embedded questions) that required patients to complete the percentage of time they were troubled by something (daily activity limitations/emotional troubles). These items yielded a significant amount of missing or inconsistent data (50%). The resulting factor analysis suggested four domains: symptoms, daily life impact, psychosocial impact, and treatment satisfaction. When included as separate scales, the symptom-bother and symptom-frequency scales were highly correlated (> 0.9). As a consequence, and due to superior discriminative validity, the symptom bother and frequency items were summed. All items met the tests for item convergent validity (item-scale correlation = 0.4). The success rate for item discriminant validity testing was 97% (item-scale correlation greater with own scale than with any other). The criterion for internal consistency reliability (alpha coefficient > or = 0.70) was met for all EAPIQ scales (range 0.89-0.93), as was the criterion for test-retest reliability (intraclass correlation [ICC] > or = 0.70). Largely moderate correlations between the scales of the EAPIQ and the mini Rhinoconjunctivitis Quality of Life Questionnaire (miniRQLQ) and low correlations with the Health Utilities Index 2/3 (HUI2/3) were indicative of satisfactory concurrent validity. The EAPIQ symptoms, Daily Life Impact, and Psychosocial Impact scales were able to distinguish between patients differing in eye allergy symptom severity, as rated by patients and clinicians, providing evidence of satisfactory known-group and clinical validities, respectively. Preliminary analyses indicated the EAPIQ Symptoms, Daily Life Impact, and Psychosocial Impact scales to be responsive to changes in eye allergies. CONCLUSION: Following item reduction, construct validity, reliability, concurrent validity, known-group validity, and preliminary responsiveness were satisfactory for the EAPIQ in this population of ocular allergy patients.

Adult↗

Health related quality of life of adolescents in Vietnam: cross-cultural adaptation and validation of the Adolescent Duke Health Profile.

Quality of life (QOL) of adolescents has been scarcely documented in a general population sample. The study was aimed at translating and adapting the Adolescent Duke Health Profile to Vietnamese, validating the questionnaire, determining reference value, and identifying determinants of poor QOL. Following a cross-cultural methodology, the Adolescent Duke Health Profile (ADHP) had content adapted to Vietnamese by alteration of 2 out of 17 items. Test-retest validity was checked in 408 adolescents. Construct validity and internal consistency were assessed in a 1408 probability sample of adolescents in Vietnam, and determinants were analysed by multiple linear regression. The ADHP showed satisfactory internal consistency (Cronbach's alpha=0.87-0.92) and satisfactory construct validity in relation with drug abuse or not, or with parent situation living in couple or alone. Test-retest reliability was acceptable (ICC=0.7-0.8) and major determinants were age, sex, education, chronic disease, alcohol and drug use. This works provide a validated, simple health related QOL scale suited to adolescent population with reference values. Taking into account determinants identified will help program prevention and intervention health policy and to evaluate the effect of these actions.

Adolescent↗

Measures used to assess burden among caregivers of stroke patients: a review.

OBJECTIVE: To describe measures used to evaluate the burden of caregiving experienced by caregivers of stroke patients and their clinimetric properties. DESIGN: A review of the literature was conducted to examine burden scales with regard to concept, feasibility, internal consistency, validity, reliability and responsiveness. RESULTS: The literature search resulted in 45 measures of caregiver outcomes, including 16 different measures of caregiver burden. About half of the scales were used only once and were not further described. Nearly all instruments measure the various dimensions of burden (competency, negative feelings, social relations, participation problems, physical and mental health and economic aspects), but not in the same proportions. Most measures showed good internal consistency, and validity was demonstrated for all measures except one. However, not much is known about the reliability and responsiveness of these measures. CONCLUSIONS: No measure has proven superiority above others. Future research should focus on comparisons between existing instruments and on their reliability and responsiveness.

Caregivers↗

How generalizable are the effects of smoking prevention programs? Refusal skills training and parent messages in a teacher-administered program.

This study investigated both substantive and methodological issues associated with school-based smoking prevention programs. Substantive issues included the efficacy of a refusal skills training curriculum and of parent messages mailed to students' homes. Methodological issues included the effects of assigning classrooms versus entire schools to experimental conditions and determination of the effects of attrition on internal and external validity. Results revealed differential impact for different subgroups of adolescents. The refusal skills program produced lower rates of smoking than the control condition for students who were smokers at the pretreatment assessment but may have produced detrimental effects among males who were nonsmokers at pretest. The provision of parent messages did not affect outcome. Method of assignment (schools versus classrooms) failed to produce significant effects, and attrition did not affect internal validity. However, the above differential findings, as well as the impact of attrition on external validity, raise questions concerning the generalizability of smoking prevention programs.

Adolescent↗

Assessing adherence to the evidence base in the management of poststroke dysphagia.

OBJECTIVE: To evaluate the reliability and responsiveness to change of an audit tool to assess adherence to evidence of effectiveness in the speech and language therapy (SLT) management of poststroke dysphagia. DESIGN: The tool was used to review SLT practice as part of a randomized study of different education strategies. Medical records were audited before and after delivery of the trial intervention. SETTING: Seventeen SLT departments in the north-west of England participated in the study. SUBJECTS: The assessment tool was used to assess the medical records of 753 patients before and 717 patients after delivery of the trial intervention across the 17 departments. A target of 10 records per department per month was sought, using systematic sampling with a random start. ANALYSIS: Inter- and intra-rater reliability were explored, together with the tool's internal consistency and responsiveness to change. RESULTS: The assessment tool had high face validity, although internal consistency was low (ra = 0.37). Composite scores on the tool were however responsive to differences between SLT departments. Both inter- and intra-rater reliability ranged from 'substantial' to 'near perfect' across all items. CONCLUSIONS: The audit tool has high face validity and measurement reliability. The use of a composite adherence score should, however, proceed with caution as internal consistency is low.

Deglutition Disorders↗

Development and psychometric evaluation of the ICIQ Vaginal Symptoms Questionnaire: the ICIQ-VS.

OBJECTIVES: To develop and validate a self-completion questionnaire for comprehensive assessment of the severity and impact of vaginal symptoms and related sexual matters, particularly those attributed to pelvic organ prolapse. To provide an instrument that can characterise the severity of these symptoms, measure their impact and evaluate treatment outcome. DESIGN: Prospective development of the content of the questionnaire and testing of its psychometric properties including validity. SETTING: Two hospital-based urogynaecology clinics and one community general practice in the South of England. POPULATION: One hundred and forty-one urogynaecology clinic attendees with varying degrees of pelvic organ prolapse and 77 randomly selected women registered with a general practice. METHODS: The questionnaire was developed through a literature review, consultation with clinicians and health scientists and structured interviews with patients. Content validity, construct validity, stability, internal consistency and sensitivity to change were examined by comparing the responses from the urogynaecology clinic with responses from the general community. Sensitivity to change was assessed using responses from women undergoing surgical treatment for pelvic organ prolapse before and 3 months after surgery. A final version of the questionnaire was obtained after factor analysis to assist item reduction and refinement of the scoring system. MAIN OUTCOME MEASURES: Content validity, construct validity, stability (test-retest reliability), internal consistency and sensitivity to change. RESULTS: The questionnaire exhibited good validity, reliability and sensitivity to change. Excellent internal consistency was demonstrated for vaginal (Cronbach's alpha 0.79) and sexual (Cronbach's alpha 0.84) symptoms. Reliability was good. The questionnaire was able to identify changes in symptoms following surgical treatment. The final ICIQ-VS questionnaire had 14 items and a simple scoring system. CONCLUSION; The ICIQ-VS self-completion questionnaire meets the need for a robust instrument for assessing a range of vaginal and sexual symptoms, in particular those of pelvic organ prolapse. It will be of use in both routine clinical practice and epidemiological research, particularly when there is a need to assess the severity of these symptoms or the efficacy of treatment.

Adult↗

Validation of a questionnaire measuring patient satisfaction with general practitioner services.

BACKGROUND: In order that patient satisfaction may be assessed in a meaningful way, measures that are valid and reliable are required. This study was undertaken to assess the construct validity and internal reliability of the previously developed Patient Satisfaction Questionnaire (PSQ). METHOD: A total of 1390 patients from five practices in the North of England, the Midlands, and Scotland completed the questionnaire. Responses were checked for construct validity (including confirmatory factor analysis to check the factor structure of the scale) and internal reliability. RESULTS: Confirmatory factor analysis showed that items loaded on the appropriate factors in a five factor model (doctors, nurses, access, appointments, and facilities). Scores on the specific subscales showed highly significant positive correlations with general satisfaction subscale scores suggesting construct validity. Also, the prediction (derived from past research) that older people would be more satisfied with the service was borne out by the results (F (4, 1312) = 57.10; p < 0.0001), providing further construct validation. The five specific subscales (doctors, nurses, access, appointments, and facilities), the general satisfaction subscale, and the questionnaire as a whole were found to have high internal reliability (Cronbach's alpha = 0.74-0.95). CONCLUSION: The results suggest that the PSQ is a valid and internally reliable tool for assessing patient satisfaction with general practitioner services.

Factor Analysis, Statistical↗

Conceptualization and measurement of getting lost behavior in persons with early dementia.

BACKGROUND: The primary purpose of this preliminary research was to describe the psychometric properties of a newly-developed Everyday Spatial Questionnaire for Dementia-patient version (ESQD-P) in a Chinese population. A secondary goal was to assess the relationship between executive functions and wayfinding strategy application. The ESQD-P is a measure for the phenomenon of 'getting lost behavior' (GLB) reported by early Alzheimer's disease sufferers, based on the concept of spatial problem-solving. METHODS: With a cross-sectional descriptive design, the ESQD-P was validated by examining for internal consistency, construct validity, concurrent validity, and exploratory factor analyses among 116 outpatients in the memory disorder clinic of a veterans' general hospital in Taiwan. Other variables included were: global cognition, measured by the Cognitive Abilities Screening Instrument; stages of dementia, measured by the Clinical Dementia Rating Scale; and depressive symptoms, measured by the Geriatric Depression Scale-Short Form. RESULTS: Findings indicated that the Chinese ESQD-P is a reliable instrument for measuring GLB (internal consistency alpha = 0.73). A five-factor solution explained 55.45% of the score variance, while the correlations between the patient and proxy versions of this instrument yielded an acceptable concurrent validity. Executive functions can predict both global and analytic wayfinding strategies. CONCLUSIONS: GLB may be explained in part by declining executive functions. Deleting the coping strategies subscale may improve psychometric properties of the ESQD-P.

Aged↗

Reliability of the Spanish version of a brief questionnaire on patient satisfaction with gastrointestinal endoscopy.

BACKGROUND: There has not been a validated questionnaire available in Spanish to evaluate patient satisfaction with gastrointestinal endoscopy. Our aim was to evaluate the external validity and internal consistency of the Spanish version of a questionnaire on patient satisfaction with gastrointestinal endoscopy elaborated by the American Society for Gastrointestinal Endoscopy. DESIGN: Prospective questionnaire validation study. PATIENTS AND METHODS: A total of 485 consecutive patients referred to two different hospitals for endoscopy were interviewed by telephone. Internal consistency was studied using Cronbach's alfa test and corrected item-total correlations (CITC). External validity was determined using a mailed questionnaire completed by 185 patients-correlations between telephone and postal responses were calculated, as well as the correlation with the total score obtained. RESULTS: Cronbach's alfa was 0.82 and mean CITC was 0.59. Weighted kappa values for the same questionnaire items performed by telephone or mail varied between 0.51 and 0.81. Total score correlation was 0.78. Internal consistency and external validity were not affected by differences in the administration of the questionnaire (mail or by telephone), different interviewers, type of endoscopy, or source of patients. CONCLUSIONS: The Spanish version of the ASGE questionnaire on satisfaction with endoscopy is valid, reliable, and reproducible.

Endoscopy, Gastrointestinal↗

Quality of reporting of observational longitudinal research.

Observational longitudinal research is particularly useful for assessing etiology and prognosis and for providing evidence for clinical decision making. However, there are no structured reporting requirements for studies of this design to assist authors, editors, and readers. The authors developed and tested a checklist of criteria related to threats to the internal and external validity of observational longitudinal studies. The checklist criteria concerned recruitment, data collection, biases, and data analysis and descriptive issues relevant to study rationale, study population, and generalizability. Two raters independently assessed 49 randomly selected articles describing stroke research published from 1999 to 2003 in six journals: American Journal of Epidemiology, Journal of Epidemiology and Community Health, Stroke, Annals of Neurology, Archives of Physical Medicine and Rehabilitation, and American Journal of Physical Medicine and Rehabilitation. On average, 17 of the 33 checklist criteria were reported. Criteria describing the study design were better reported than those related to internal validity. No relation was found between study type (etiologic or prognostic) or word count and quality of reporting. A flow diagram for summarizing participant flow through a study was developed. Editors and authors should consider using a checklist and flow diagram when reporting on observational longitudinal research.

Epidemiology↗