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At least 1,153 records · Page 64Linked to original sources
PubMed2005

The impact of obesity on technical feasibility and postoperative outcomes of laparoscopic left colectomy.

OBJECTIVE: To compare technical aspects and postoperative outcomes of laparoscopic left colectomy in obese and nonobese patients. SUMMARY BACKGROUND DATA: Obesity has been generally associated with increased surgical risk. The data regarding outcomes after laparoscopic colectomy in obese and nonobese patients are limited and quite controversial; however, most reports have suggested that obesity is associated with a greater technical difficulty as well as an increased risk for conversions and postoperative complications. METHODS: All patients undergoing laparoscopic left colectomy for any pathologic condition between January 2001 and January 2003 were analyzed. Patients with a body mass index (BMI) above 30 kg/m were defined as obese and patients with BMI below 30 kg/m were defined as nonobese. Data collected included age, gender, BMI, American Society of Anesthesiologists score, diagnosis, technical parameters of the procedure, operative time, conversion, pathology, length of hospital stay, and complications over a 30-day postoperative course. RESULTS: A total of 123 patients underwent elective laparoscopic left colectomy during the 2-year period. Twelve patients were excluded from analysis because missing data did not allow calculation of their BMI. Of the 111 patients analyzed, 23 (20.7%) were obese and 88 patients (79.3%) were nonobese. Patients' preoperative clinical characteristics were similar in obese and nonobese patients except for BMI (P > 0.001). There were no significant differences between the 2 groups with respect to intraoperative parameters, duration of the operation, resection margin, and number of harvested nodes as well as overall postoperative complication rates. There were no conversions in the obese patients, whereas 5 procedures in the nonobese group required conversion to open surgery (P = not significant). Obese patients had shorter hospital stays than nonobese subjects (7 +/- 2.5 days vs. 9.5 +/- 7 days; P = 0.018). CONCLUSION: In contrast with previously reported series of laparoscopic colectomy, our findings show that obesity does not have an adverse impact on the technical difficulty and postoperative outcomes of laparoscopic left colectomy. Our study supports the safety of using laparoscopic surgery for colorectal diseases in obese patients.

Aged↗
PubMed2026

Cardiometabolic Multimorbidity Increases the Risk of Hip Fracture: A Longitudinal Cohort Study Based on CHARLS.

BACKGROUND: Cardiometabolic Multimorbidity (CMM) is defined as the co-occurrence of two or more conditions among heart disease, diabetes mellitus, stroke, and hypertension. Previous studies have shown associations between cardiometabolic diseases and fragility fractures; however, the relationship between CMM and hip fractures remains unclear in the Chinese population. This study therefore aims to investigate this association in a Chinese cohort to inform fracture prevention strategies. METHODS: This prospective cohort study used data from the China Health and Retirement Longitudinal Study (CHARLS) collected from 2011 to 2020. Participants from the 2011 baseline survey cohort were initially included. Subsequently, individuals were sequentially excluded if they were under 45 years of age, had incomplete baseline CMM information, had a history of hip fracture, lost to follow-up, or had missing data on confounders. Kaplan-Meier survival analysis, Cox proportional hazards regression, subgroup analyses, and sensitivity analyses were performed to evaluate the association between CMM and the risk of hip fracture. RESULTS: A total of 6314 participants aged 45 years and older were included, of whom 544 had CMM. Over a 9-year follow-up period, 287 incident hip fractures (4.55%) were identified. Among these, 36 participants had been diagnosed with CMM at baseline, whereas 251 had not. The incidence of hip fracture was significantly higher in participants with CMM than in those without CMM (13% vs. 8%, p = 0.015). After full adjustment for confounders, multivariable Cox regression showed that CMM was associated with a 70% increased risk of hip fracture (HR = 1.70, 95% CI: 1.318-2.47; p = 0.005). Subgroup analyses indicated that age and history of falls were significant effect modifiers. The association between CMM and hip fracture was more pronounced in participants under 60 years old (P for interaction = 0.048) and those with a history of falls (P for interaction = 0.014). CONCLUSION: These findings suggest that CMM increases the risk of hip fracture, particularly among relatively younger individuals and those with a history of falls.

Humans↗
PubMed2004

Sensitivity analysis of longitudinal normal data with drop-outs.

We propose to perform a sensitivity analysis to evaluate the extent to which results from a longitudinal study can be affected by informative drop-outs. The method is based on a selection model, where the parameter relating the dropout probability to the current observation is not estimated, but fixed to a set of values. This allows to evaluate several hypotheses for the degree of informativeness of the drop-out process. Expectation and variance of missing data, conditional on the drop-out time are computed, and a stochastic EM algorithm is used to obtain maximum likelihood estimates. Simulations show that when the drop-out parameter is correctly specified, unbiased estimates of the other parameters are obtained, and coverage percentages of their confidence intervals are close to their theoretical value. More interestingly, misspecification of the drop-out parameter does not considerably alter these results. This method was applied to a randomized clinical trial, designed to demonstrate non-inferiority of an inhaled corticosteroid in terms of bone density, compared with a reference treatment. Sensitivity analysis showed that the conclusion of non-inferiority was robust against different hypotheses for the drop-out process.

Adolescent↗
PubMed2003

Evaluating a practice-oriented service model to increase the use of respite services among minorities and rural caregivers.

PURPOSE: The goal of this study was to evaluate the practice-oriented model of service use (Yeatts, Crow, & Folts, 1992) relative to the more widely used behavioral model ( Andersen, 1968) in its ability to explain the use of respite services by caregivers of Alzheimer's patients. Unlike the behavioral model, which focuses primarily on characteristics of the service user, the practice-oriented model focuses primarily on characteristics of the service. DESIGN AND METHODS: Interview data from 1,158 caregivers participating in the Alzheimer's Disease Demonstration Grants to States program ( Montgomery, Kosloski, Karner, & Schaefer, 2002) were analyzed. Separate regression models were estimated for adult day care and in-home respite, using the full information maximum likelihood procedure described by Arbuckle (1996), and ordinary least squares regression with listwise deletion of missing data. RESULTS: The findings indicate that the factors related to respite use tapped by the practice-oriented model add significantly to explanatory models of service use over models that use only the factors typically represented by the behavioral model. Additional analyses, including a set of interactions with ethnicity, indicated that this improvement occurs primarily for White and Hispanic caregivers, and less so for African Americans. IMPLICATIONS: The findings are discussed in terms of their implications for enhancing the timely use of respite services and directions for future research.

Alzheimer Disease↗
PubMed2000

Assessing research outcomes by postal questionnaire with telephone follow-up. TOTAL Study Group. Trial of Occupational Therapy and Leisure.

BACKGROUND: Face-to-face assessment of research outcomes is expensive and may introduce bias. Postal questionnaires offer a cheaper alternative which avoids observer bias, but non-response and incomplete response reduce the effective sample size and may be equally serious sources of bias. This study examines the extent and potential effects of missing data in the postal collection of outcomes for a large rehabilitation trial. METHODS: Questionnaires containing a number of established scales were posted to participants in a trial of occupational therapy after stroke. Response was maximized by telephone and postal reminders, and incomplete questionnaires were followed up by telephone. Scale scores obtained by imputing values to questionnaire items missing on return were compared with those achieved by telephone follow-up. FINDINGS: Response to the initial posting was 60%, rising to 85% after reminders. Participants receiving the experimental treatment were more likely to respond without a reminder. There were no significant differences on any known factors between eventual responders and non-responders. Of the questionnaires, 43% were incomplete on return: partial responders were significantly different to complete responders on baseline disability and home circumstances. Of the incomplete questionnaires, 71% were resolved by telephone follow-up. In these, the scale scores achieved by telephone were generally higher than those derived by conventional imputation. CONCLUSION: Postal outcome assessment achieved a good response rate, but considerable effort was needed to minimize non-response and incomplete response, both of which could have been serious sources of bias.

Bias↗
PubMed1996

Physical activity and stroke incidence in women and men. The NHANES I Epidemiologic Follow-up Study.

To test the hypothesis that physical inactivity is associated with increased stroke risk in women and men, the authors analyzed data from a longitudinal cohort study with three follow-up data collection waves. In the Nation Health and Nutrition Examination Survey I (NHANES I) Epidemiologic Follow-up Study, 7,895 white persons and black persons aged 45-74 years were examined in 1971-1975 as part of NHANES I. Included in this analysis were 5,852 persons without a history of stroke (fatal and nonfatal) or missing data. The average follow-up was 11.6 years (maximum, 16.4 years). Incident stroke (fatal or nonfatal) was the main outcome measure. Events were ascertained from cause of death information coded from death certificates and from discharge diagnoses coded from hospital and nursing home records during the follow-up period (1971 through 1987). Participants were asked to characterize their level of habitual physical activity as low, moderate, of high. The relative risk for stroke was estimated by Cox proportional hazards regression analysis, comparing persons reporting low with those reporting high physical activity at baseline and persons in the upper with those in the lower tertile of resting pulse rate. There were 249 incident cases of stroke identified in white women, 270 in white men, and 104 in blacks. In white women aged 65-74 years, low nonrecreational activity was associated with an increased risk of stroke (relative risk = 1.82,95% confidence interval 1.10-3.02) after adjusting for the baseline risk factors of age, smoking, history of diabetes, history of heart disease, education, systolic blood pressure, serum total cholesterol, body mass index, and hemoglobin concentration. Similar associations were seen for men and for blacks and for low recreational activity in women. A higher resting pulse rate was associated with an increased risk of stroke in blacks but not in whites. A consistent association of reported low physical activity with an increased risk of stroke was observed in white women. Regular physical activity may be of benefit in preventing stroke in women as well as men.

Age Distribution↗
PubMed2005

A prospective study of calf factors affecting age, body size, and body condition score at first calving of holstein dairy heifers.

Data were collected prospectively on parameters related to first calving on 18 farms located in Northeastern Pennsylvania. This project was designed to study possible residual effects of calf management practices and events occurring during the first 16 wk of life on age, BW, skeletal growth, and body condition score at first calving. Multiple imputation method for handling missing data was incorporated in these analyses. This method has the advantage over ad hoc single imputations because the appropriate error structure is maintained. Much similarity was found between the multiple imputation method and a traditional mixed model analysis, except that some estimates from the multiple imputation method seemed more logical in their effects on the parameter measured. Factors related to increased age at first calving were increased difficulty of delivery, antibiotic treatment of sick calves, increased amount of milk or milk replacer fed before weaning, reduced quality of forage fed to weaned calves, maximum humidity, mean daily temperature, and maximum ammonia levels in calf housing areas. Body weight at calving tended to increase with parity of the dam, increased amount of grain fed to calves, increased ammonia levels, and increased mean temperature of the calf housing area. Body condition score at calving tended to be positively influenced by delivery score at first calving, dam parity, and milk or milk replacer dry matter intake. Withers height at calving was positively affected by treatment of animals with antibiotics and increased mean temperature in the calf area. This study demonstrated that nutrition, housing, and management factors that affect health and growth of calves have long-term effects on the animal at least through first calving.

Aging↗
PubMed1981

Validity and reliability of a high school drug use questionnaire among Mexican students.

This study was carried out to ascertain the validity and reliability of data generated through an internationally developed self-administered questionnaire. Data were collected from two student populations in which prevalence of drug use was known (high and low prevalence rates) and information obtained from the questionnaire checked through personal interview. The questionnaire covered both demographic characteristics and drug use items. A total of 474 students were tested and 335 students (70.7 per cent) retested. Although percentages of missing data and inconsistent responses were high, the questionnaire appeared valid and reliable when analysed on a group basis. It was less reliable on an individual basis. In conclusion, it is considered that with minor modifications the questionnaire can be used in the populations studied with enough confidence in validity and reliability to allow comparisons.

Adolescent↗
PubMed2005

The validity of searching routinely collected general practice computer data to identify patients with chronic kidney disease (CKD): a manual review of 500 medical records.

BACKGROUND: We conducted a search of 12 practices' routinely collected computer data in three localities across the UK and found that 4.9% of the registered population had an estimated glomerular filtration rate (GFR) of <60 ml/min/1.73 m(2) (equivalent to stages 3-5 CKD). Only 3.6% of these were known to have renal disease. Although UK general practice is computerized, important clinical data might be recorded in letters or free-text computer entries and might therefore be invisible to the standard computer search tools. We therefore manually searched through all the records of patients with stages 3-5 CKD in one practice, to test the validity of the computer generated diagnosis and to see if other relevant information was missed by the computer search. METHODS: We identified 492 people with stages 3-5 CKD using computer searching and then manually searched their computer records and written notes for any missed data. The dataset included cardiovascular morbidities and risk factors including diabetes; drugs which may impair renal function; known renal disease; and terminal diagnoses and dementia. RESULTS: The manual searches only added four renal diagnoses to the 36 already identified. Although heart failure and stroke appear to be over-estimated by computer searches, other cardiovascular diagnoses were reliably recorded. Cardiovascular risk factors and drug recording is a strength of general practice computer data. It is complete and contemporary, though most patients had scope to have their cardiovascular risk reduced further. Eighty-four percent had a haemoglobin estimation, and a higher proportion with reduced renal function were anaemic (P<0.001). Testing for proteinuria was less well recorded; negative stick tests were not recorded. Clinical diagnoses of prostatism and bladder outflow problems made these data hard to interpret. CONCLUSIONS: Automated searching of general practice computer records could provide a reliable and valid way of identifying people with stages 3-5 CKD who could benefit from interventions readily available in primary care.

Adult↗
PubMedDate not supplied

Multivariate Bayesian analysis of Gaussian, right censored Gaussian, ordered categorical and binary traits using Gibbs sampling.

A fully Bayesian analysis using Gibbs sampling and data augmentation in a multivariate model of Gaussian, right censored, and grouped Gaussian traits is described. The grouped Gaussian traits are either ordered categorical traits (with more than two categories) or binary traits, where the grouping is determined via thresholds on the underlying Gaussian scale, the liability scale. Allowances are made for unequal models, unknown covariance matrices and missing data. Having outlined the theory, strategies for implementation are reviewed. These include joint sampling of location parameters; efficient sampling from the fully conditional posterior distribution of augmented data, a multivariate truncated normal distribution; and sampling from the conditional inverse Wishart distribution, the fully conditional posterior distribution of the residual covariance matrix. Finally, a simulated dataset was analysed to illustrate the methodology. This paper concentrates on a model where residuals associated with liabilities of the binary traits are assumed to be independent. A Bayesian analysis using Gibbs sampling is outlined for the model where this assumption is relaxed.

Bayes Theorem↗
PubMed2006

Applying the item response theory to classroom examinations.

OBJECTIVE: The purpose of this research project was to determine if the item response theory (IRT) can successfully be applied to smaller-sized class examinations. METHODS: The Rasch mathematical model (RMM) was selected from the family of IRT models because of its ability to work with smaller sample sizes. Two simulated examinations were created for 100 students by 100-item dichotomous examinations. Examination 2 contained 20 items common with those in examination 1. Examination 1 was systematically exposed to randomly missing student responses and to entire items being removed to determine the robustness of the RMM to missing data. The two examinations were then analyzed with the RMM individually and then in combination. Student scores and IRT measures were compared to determine if the IRT could successfully place the students from the two examinations on the same metric of measure. RESULTS: The student measures were not affected when up to 20% of the student responses were randomly missing. Student measures continued to have high reliability and correlated with full matrix measures for up to 40% of items being dropped from the examination. Student scores and IRT measures correlated highly when the two examinations were combined. CONCLUSIONS: The RMM can be successfully applied to small-sized class examinations, such as those at chiropractic, medical, and other health profession institutions. It is possible to place candidates from different administrations on the same metric of measure if there is as little as a 20% overlap of items between examinations. The RMM could assist faculty in determining if differences in candidate scores are caused by ability or item difficulty.

Chiropractic↗
PubMed2000

Rivastigmine for Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the most common cause of dementia in the elderly. One of the most successful therapeutic strategies for Alzheimer's disease has been the use of acetylcholinesterase inhibitors to enhance surviving cholinergic neurotransmission by inhibiting breakdown of released acetylcholine. The first generation acetylcholinesterase inhibitors, such as tacrine, revealed major limitations to use including hepatotoxicity. Several second generation acetylcholinesterase inhibitors have now been introduced, including rivastigmine, which are believed to have superior proprieties. The mode of action and metabolism of rivastigmine suggest that it is unlikely to interact significantly with other medications. This is of particular relevance in elderly AD patients, the majority of whom are likely to be receiving concomitant medication. Large multi-centre trials have been completed in the USA, Canada, Europe and South Africa. Rivastigmine has received EU approval for use in all member states. It has approval in 30 countries but not the US. It is currently under review by the Food and Drug Administration, who requested additional analyses in 1998. OBJECTIVES: To determine the clinical efficacy and safety of rivastigmine for patients with dementia of the Alzheimer's type. SEARCH STRATEGY: The Cochrane Controlled Trials Register, the Dementia Group Register of Clinical Trials, other electronic databases and other sources of reports were searched using the terms ENA 713, EXELON, and rivastigmine in addition to the terms for controlled trials in dementia (see the Group's search strategy for full details). SELECTION CRITERIA: All unconfounded, double-blind, randomised trials in which treatment with rivastigmine was administered for more than one day and compared to placebo for patients with dementia of the Alzheimer's type. DATA COLLECTION AND ANALYSIS: Data were extracted by the reviewer (JSB) and entered into an appropriate meta-analysis. The data extracted were cross-checked by the second reviewer (VI). For each outcome measure, data were sought on every patient randomised. To allow an intention-to-treat analysis, the data were sought irrespective of compliance, whether or not the patient was subsequently deemed ineligible, or otherwise excluded from treatment or follow-up. If these data were not available, an analysis of data on patients who completed treatment was conducted. MAIN RESULTS: There are seven included trials. There are no published reports for two large phase III trials, B304 and B351, although they were completed more than 3 years ago. These are part of the Novartis ADENA programme and comprise 1379 (49%) out of 2803 phase III patients. It is unclear how missing data are replaced in ITT analyses, as reports from the ADENA programme provide no description of the use of this method. This has a profound effect on the results: if the method is substantially the same as LOCF, the benefits of treatment inferred from the analyses described in the publications as ITT, may be exaggerated. The meta-analysis reveals benefits on cognitive function as measured by ADAS-Cog test scores for the higher dose of rivastigmine compared to placebo at 26 weeks and for the lower dose. An additional analysis of ADAS-Cog dichotomised into those showing less than 4 points improvement and those showing 4 or more points improvement at 26 weeks shows benefit for cognitive function for the higher dose of rivastigmine compared to placebo and not for the lower dose. Global clinical state, dichotomised, counting those showing no change or decline, against those showing improvement shows benefit due to lower dose rivastigmine compared to placebo at 26 weeks and not for the higher dose. One trial reported results at 18 weeks and there are no significant differences between higher dose rivastigmine and placebo. One trial reported results at 13 weeks, and there are no significant differences between the 4 or 6 mg/d rivastigmine group and p

Alzheimer Disease↗
PubMed2004

A systematic review of the accuracy of ultrasound in the diagnosis of deep venous thrombosis in asymptomatic patients.

Evaluation of the accuracy of ultrasound has yielded heterogeneous results. Our objective was to summarize the evidence on the accuracy of ultrasound compared to venography in asymptomatic patients, taking into account the variation due to threshold differences. Searches of journal table of contents, computer databases (Medline, Embase, Biomed, Cochrane) and conference proceedings were performed. A study was eligible if it prospectively compared ultrasound to venography for the diagnosis of DVT in asymptomatic patients. Data of studies selected for inclusion were extracted independently by two authors. High quality studies with consecutive patient enrollment, blind evaluation of the two techniques, and absence of verification bias are summarized as Level 1, while those not fulfilling one or more of these criteria are considered Level 2. Original study authors were contacted to confirm accuracy and to provide missing data. A pooled estimate of the accuracy of ultrasound was obtained according to the method of Moses and coworkers. This method gives a summary diagnostic odds ratio (DOR). The DOR is a single indicator of test performance. It varies between 0 and infinity and exceeds 1, only when ultrasound is more often positive in patients with DVT relative to those without DVT. Higher DOR indicates better discriminatory test performance. Thirty one studies were rated as potentially unbiased and graded as Level 1. The mean prevalence of DVT as determined by venography was 22%. In Level 1 studies, the odds of positive ultrasound in proximal veins was 379 times higher (95% confidence limits 65, 2,200) and in distal veins 32 times higher (7.5, 135) among patients with DVT than those without. Our results suggest that, particularly for proximal veins, ultrasound is accurate for the diagnosis of DVT in asymptomatic postoperative orthopedic patients. More research is needed in other clinical settings.

Humans↗
PubMed2004

Usability of a computer-assisted interview system for the unaided self-entry of patient data in an urban rheumatology clinic.

OBJECTIVE: This study quantified the ease of use for patients and providers of a microcomputer-based, computer-assisted interview (CAI) system for the serial collection of the American College of Rheumatology Patient Assessment (ACRPA) questionnaire in routine outpatient clinical care in an urban rheumatology clinic. DESIGN: A cross-sectional survey was used. MEASUREMENTS: The answers of 93 respondents to a computer use questionnaire mailed to the 130 participants of a previous validation study of the CAI system were analyzed. For a 30-month period, the percentage of patient visits during which complete ACRPA questionnaire data were obtained with the system was determined. RESULTS: The computer system provided cost and labor savings in the collection of 2,476 questionnaires for 2,964 patients visits over 30 months for a capture rate of 83.5%. In the last 12 of those months, 1,035 questionnaires were collected for 1,062 patient visits (97.5% capture). There were no missing data. The prestudy capture rate was 13.5%, with 33% of surveys having complete data. Patients rated the overall usability of the system as good (mean = 1.34, standard deviation = 0.61) on a scale of 0-2, where 2 = good, but expressed difficulty with mouse manipulation and concerns about the privacy of the data entry environment. CONCLUSION The system proved easy to use and cost-effective for the (mostly) unaided self-entry of self-report data for each patient for each visit in routine outpatient clinical care in an urban rheumatology clinic.

Attitude to Computers↗
PubMedDate not supplied

Practical issues in quality of life assessment in multicentre trials conducted by the Swiss Group for Clinical Cancer Research.

Quality of life (QOL) assessment has become an integrated part in some advanced disease trials and to a lesser extent in early disease trials conducted by the Swiss Group for Clinical Research (SAKK). In general, the concept of QOL endpoints and the additional work of collecting these data is well accepted by patients, nurses and physicians. The QOL form submission rates in recently completed trials in advanced disease have improved in response to ongoing staff training and supervision as well as direct and personal interventions in the local centres, with 82-86 per cent before treatment failure, and 59-88 per cent at failure. The main source of missing data are local administrative problems, in particular staff oversights.

Clinical Trials as Topic↗
PubMed2005

High prevalence of overweight among pediatric users of community health centers.

OBJECTIVE: With the increasing prevalence of pediatric obesity, it is important to identify high-risk populations of children to direct limited resources for prevention and treatment to those who are most vulnerable. The objectives of this study were to determine the prevalence of overweight in children who are clients of community health centers in medically underserved areas of the Health Resources and Service Administration regions II and III (Mid-Atlantic and Puerto Rico), compare this prevalence to nationally representative data, and contrast prevalence data between geographic areas and racial/ethnic groups. METHODS: The charts from a representative sample of 2474 children using 30 community health centers in 2001 were abstracted to collect clinically measured weight and height. Overweight was defined as a body mass index of > or =95th percentile of a reference population. To generate an unbiased estimate of overweight, multiple imputations were used for missing data. These data were compared with the 1999-2002 National Health and Nutrition Examination Survey. RESULTS: The prevalence of overweight was elevated in this sample of children aged 2 to 5 years (21.8%; 95% confidence interval [CI]: 19.1-24.8) and 6 to 11 years (23.8%; 95% CI: 16.9-27.7) compared with the 1999-2002 National Health and Nutrition Examination Survey (10.3% and 15.8%, respectively). No significant differences in prevalence were observed between Asian American (18.2%; 95% CI: 11.2-28.3), Hispanic (24.6%; 95% CI: 21.3-28.2), non-Hispanic black (25.6%; 95% CI: 20.8-30.9), and non-Hispanic white (22.8%; 95% CI: 19.0-27.0) children. Furthermore, no differences in prevalence were observed between children using community health centers in continental urban (23.7%; 95% CI: 20.6-27.2), suburban (24.0%; 95% CI: 20.0-28.5), or rural (22.9%; 95% CI: 19.3-26.9) areas. CONCLUSIONS: The present study identified a population of children at particularly high risk for obesity based on the type of health care delivery system they use regardless of race/ethnicity or geographic characteristics. Because community health centers are experienced in prevention and serve >4.7 million children in the United States, they may be a particularly promising point of access and setting for pediatric obesity prevention.

Child↗
PubMed2005

The OutPatient Experiences Questionnaire (OPEQ): data quality, reliability, and validity in patients attending 52 Norwegian hospitals.

OBJECTIVE: To describe the development and evaluation of the OutPatient Experiences Questionnaire (OPEQ) for somatic outpatients. DESIGN: Literature review, patient interviews, pretesting of questionnaire items, and a cross sectional survey. SETTING: Postal survey of adult outpatient clinics at 52 hospitals in all five regions of Norway during 2003 and 2004. SUBJECTS: 35,719 patients who had attended an outpatient clinic within the previous 3 weeks. RESULTS: 19,266 patients (53.9%) responded to the questionnaire. Low levels of missing data suggest that the questionnaire is acceptable to patients. Factor analysis of items applicable to all patients produced three factors: clinic access (two items), communication (six items), and organisation (four items). The remaining items contributed to the hypothesised scales of hospital standards (three items), information (six items), and pre-visit communication (three items). With the exception of the pre-visit communication scale, the levels of Cronbach's alpha were >0.7. With the exception of the hospital standards scale, all produced test-retest correlations that exceeded 0.7. Most of the results of validity testing were as hypothesised. Correlations between the OPEQ scores ranged from 0.30 (clinic access and hospital standards) to 0.73 (communication and information). As hypothesised, scores were significantly related to patient responses to questions about overall satisfaction, general health and age. CONCLUSIONS: The OPEQ is a self-administered questionnaire that includes the most important aspects of patient experience from an outpatient perspective. It has good evidence for internal consistency, test-retest reliability, and validity.

Adolescent↗
PubMed2001

Sensitivity analysis of longitudinal binary quality of life data with drop-out: an example using the EORTC QLQ-C30.

Analysing quality of life data (QOL) may be complicated for several reasons. Quality of life data not only involves repeated measures but is also usually collected on ordered categorical responses. In addition, it is evident that not all patients provide the same number of assessments, due to attrition caused by death or other medical reasons. In the recent statistical literature, increasing attention is given to methods which can handle non-continuous outcomes in the presence of missing data. The aim of this paper is to investigate the effect on statistical conclusions of applying different modelling techniques to QOL data generated from an EORTC phase III trial. Treatment effects and treatment differences are of major concern. First, a random-effects model is fitted, relating a binary longitudinal response (derived from the physical functioning scale of the QLQ-C30) to several covariates. In a second approach, marginal models are fitted, retaining the response variable and the mean structure used before. The fitted marginal models only differ with respect to the considered estimation procedure: generalized estimating equations (GEE); weighted generalized estimating equations (WGEE), and maximum likelihood (ML).

Antibiotics, Antineoplastic↗