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PubMed2002

Development of Japanese version of the UCLA Prostate Cancer Index: a pilot validation study.

METHODS: The Japanese version (version 1.2) of the UCLA PCI was developed through a process of translation, back-translation, and refinement after interviewing patients. Reliability and validity were examined for 125 Japanese patients with localized prostate cancer. The patients simultaneously responded to the Japanese version of the RAND 36-Item Health Survey (SF-36) and five representative questions from the International Index of Erectile Function (IIEF). RESULTS: Internal consistency reliability was very high for both urinary and sexual function scales, and lower for bowel function. The test-retest reliability of the urinary and sexual function scales and the urinary bother scales was stable, while that of the bowel function and bother scales was relatively unstable. Sexual function scores did not correlate highly with sexual bother scores. Furthermore, poor sexual function and bother had little association with the SF-36 scores. Missing data as to urinary and bowel function/bother scales were minimal (0.8%-2.4%), while those for sexual function and bother were relatively high (4.8%-11.2%). CONCLUSIONS: The results of this pilot study, together with the previous American study, suggest ethnic or cultural difference in how impaired sexual function is integrated into overall QOL. A future cross-cultural comparative study using the UCLA PCI and SF-36 will provide useful information about the influence of cultural or ethnic differences on health-related QOL in prostate cancer patients.

Aged↗

PubMed2005

Quality of life of patients operated on for low rectal cancer: impact of the type of surgery and patients' characteristics.

PURPOSE: This study was designed to compare the impact of a permanent colostomy and sociodemographic characteristics on the quality of life of patients operated on for low rectal cancer. METHODS: A cross-sectional study was performed by use of the European Organization for Research and Treatment of Cancer QLQ-C30 and CR-38 questionnaires. Patients came to the hospital to fill out the self-administered questionnaire or were sent the questionnaire by mail, followed by a live or telephone interview. All patients had undergone one of four operations: low anterior resection with colorectal or coloanal anastomosis (non-stoma group), or abdominoperineal resection with pseudocontinent perineal colostomy (nonstoma group) or left lower quadrant colostomy (stoma group). RESULTS: A total of 132 patients were included for analysis and there were no missing data. For the majority of quality of life scores (26/29), there was no significant difference between stoma and nonstoma patients. However, stoma patients complained of diminished body image (P = 0.0022), and this was especially true for married (P = 0.0073) and less educated (P = 0.0014) patients at subgroup analysis. Stoma patients experienced greater financial worries (P = 0.0029), whereas nonstoma patients had greater gastrointestinal concerns (P = 0.0098). CONCLUSIONS: Although most quality of life scores between stoma and nonstoma patients were similar, significant differences regarding body image, finance, and gastrointestinal symptoms, especially for married and less educated patients, were noticed. These factors should be taken into account, along with oncologic criteria, to better tailor treatments to patients.

Adult↗

PubMed2006

A systematic review of the efficacy of cesarean section in the preservation of anal continence.

PURPOSE: Elective primary cesarean section is performed largely to avoid maternal pelvic trauma that may result in anal incontinence, although its efficacy in this regard has not been thoroughly assessed. We perform a systematic review of published reports that compare anal incontinence risk by mode of delivery. METHODS: PubMed was searched from 1966 through August 2005. Authors were contacted for missing data or analyses. Both randomized and nonrandomized reports were included. Eligible studies included females having vaginal delivery or cesarean section, fecal and/or flatal incontinence was reported as an outcome, and risk was calculable from the reported data. Crude data were extracted from the reports, as well as reported odds ratios and confidence intervals. In the nonrandomized studies, adjusted odds ratios also were extracted and additional data obtained from authors to adjust risks for age and parity if not originally done. Sensitivity analyses were performed using quality indicators: age and parity adjustment, time to continence assessment, and mode of previous delivery. RESULTS: Fifteen studies were found eligible, encompassing 3,010 cesarean sections and 11,440 vaginal deliveries. The summary relative risk for fecal incontinence was 0.91 (95 percent confidence interval, 0.74-1.14). For flatus the relative risk was 0.98 (range, 0.86-1.13). The number needed to treat by cesarean section was 167 to prevent a single case of fecal incontinence. Five studies were judged to be of high quality. In these studies, the summary relative risk was 0.94 (range, 0.72-1.22) and number needed to treat was 198. CONCLUSIONS: The best evidence to assess the efficacy of cesarean section in the prevention of anal incontinence would be in randomized trials of average-risk pregnancies with few crossovers. In the absence of such trials and based on this review, cesarean section does not prevent anal incontinence. This implies that incontinence associated with delivery may be more likely incontinence caused by pregnancy.

Cesarean Section↗

PubMed2006

Maternal use of recreational drugs and neuroblastoma in offspring: a report from the Children's Oncology Group (United States).

OBJECTIVE: To evaluate whether maternal use of recreational drugs around conception and pregnancy influences the risk of childhood neuroblastoma. METHODS: Self-reported use of recreational drugs from one month prior to pregnancy until diagnosis was assessed among mothers of 538 children with neuroblastoma (diagnosed 1992-1994 and identified through the Children's Cancer Group and Pediatric Oncology Group) and 504 age-matched controls (identified by random-digit dialing). Odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression, adjusting for age at diagnosis and household income. RESULTS: Maternal use of any illicit or recreational drug around pregnancy was associated with an increased risk of neuroblastoma in offspring (OR = 1.82, 95% CI: 1.13, 3.00), particularly use of marijuana in the first trimester of pregnancy (OR = 4.75, 95% CI: 1.55, 16.48). Marijuana use in the month before pregnancy did not increase risk. The effect of gestational marijuana exposure was strongest in subjects diagnosed before age one. Evaluation of recreational drugs other than marijuana was limited by infrequent use, and analyses of drug use by fathers were not carried out due to missing data. CONCLUSIONS: Maternal recreational drug use and marijuana use during pregnancy were associated with increased risk of neuroblastoma in offspring. Further examination of these drugs and the risk of childhood cancer is warranted.

Adolescent↗

PubMed2006

The natural progression of health-related quality of life: results of a five-year prospective study of SF-36 scores in a normative population.

BACKGROUND: Limited information exists regarding the natural progression of health-related quality of life (HRQOL) in the general population, as most research has been cross-sectional or has followed populations with specific medical conditions. Such norms are important to establish, because the effect of any intervention may be confounded by changes due to the natural progression of HRQOL over time. METHODS: Participants were randomly selected from 9 Canadian cities and surrounding rural areas. Changes in the eight domains and 2 summary component scores of the Medical Outcomes Study 36-item short form (SF-36) were examined over a 5 year period (1996/1997-2001/2002). Mean changes were calculated for men and women within 10 year age categories. Multiple imputation was used to adjust for potential selection bias due to missing data. RESULTS: The baseline sample included 6539 women and 2884 men. Loss to follow-up was 17% for women and 23% for men. Mean changes tended to be small, but there was an overall trend towards decreasing HRQOL over time. Changes were more pronounced in the older age groups and in the physically oriented domains. Younger age groups tended towards small mean improvements, particularly in the mentally oriented domains. Large standard errors suggest that on an individual level, large improvements in some participants are balanced by large declines in others. CONCLUSION: In general, the HRQOL of Canadians appears relatively stable over a 5 year period. However, care should be taken when assessing HRQOL longitudinally in certain age or gender groups, as changes associated with an intervention can potentially be confounded by the natural progression of HRQOL.

Adult↗

PubMed2006

Predictors of the extent of agreement for quality of life assessments between terminally ill cancer patients and their primary family caregivers in Taiwan.

The use of family caregivers to report patients' dying experiences has been suggested as a way of resolving the problem of non-response bias and missing data in end-of-life research. There is a dearth of information in the literature about the predictors of the extent of agreement for quality of life (QOL) assessments between patients and family informants outside of Western countries. In addition, to date there has been little progress made in deciphering meaningful influencing factors on the levels of agreement between patient and family QOL assessments. The purpose of this study was to identify the impact of the demographics and disease characteristics of patients and families, relationships of the patient to family caregiver, and caregiving burden on the extent of agreement for QOL assessments between Taiwanese terminally ill cancer patients and their family caregivers. Results from assessments by 114 dyads of Taiwanese terminally ill cancer patients and their family caregivers indicated that the extent of agreement between patient and family assessments of patient QOL was negatively influenced by the caregiving burden (amount of care needed and the impact of caregiving on caregiver's health), positively influenced by the patient's poorer health status, and there were a mixed effect of the demographics and the relationship between the patient and the family. Providing clinical care tailored at empowering families and aimed at reducing their unmet caregiving needs may improve family caregivers' abilities to assess patient QOL sensitively.

Adult↗

PubMed2006

Heart sound cancellation from lung sound recordings using time-frequency filtering.

During lung sound recordings, heart sounds (HS) interfere with clinical interpretation of lung sounds over the low frequency components which is significant especially at low flow rates. Hence, it is desirable to cancel the effect of HS on lung sound records. In this paper, a novel HS cancellation method is presented. This method first localizes HS segments using multiresolution decomposition of the wavelet transform coefficients, then removes those segments from the original lung sound record and estimates the missing data via a 2D interpolation in the time-frequency (TF) domain. Finally, the signal is reconstructed into the time domain. To evaluate the efficiency of the TF filtering, the average power spectral density (PSD) of the original lung sound segments with and without HS over four frequency bands from 20 to 300 Hz were calculated and compared with the average PSD of the filtered signals. Statistical tests show that there is no significant difference between the average PSD of the HS-free original lung sounds and the TF-filtered signal for all frequency bands at both low and medium flow rates. It was found that the proposed method successfully removes HS from lung sound signals while preserving the original fundamental components of the lung sounds.

Adolescent↗

PubMed2006

Respondent-driven sampling of injection drug users in two U.S.-Mexico border cities: recruitment dynamics and impact on estimates of HIV and syphilis prevalence.

Respondent-driven sampling (RDS), a chain referral sampling approach, is increasingly used to recruit participants from hard-to-reach populations, such as injection drug users (IDUs). Using RDS, we recruited IDUs in Tijuana and Ciudad (Cd.) Juárez, two Mexican cities bordering San Diego, CA and El Paso, TX, respectively, and compared recruitment dynamics, reported network size, and estimates of HIV and syphilis prevalence. Between February and April 2005, we used RDS to recruit IDUs in Tijuana (15 seeds, 207 recruits) and Cd. Juárez (9 seeds, 197 recruits), Mexico for a cross-sectional study of behavioral and contextual factors associated with HIV, HCV and syphilis infections. All subjects provided informed consent, an anonymous interview, and a venous blood sample for serologic testing of HIV, HCV, HBV (Cd. Juárez only) and syphilis antibody. Log-linear models were used to analyze the association between the state of the recruiter and that of the recruitee in the referral chains, and population estimates of the presence of syphilis antibody were obtained, correcting for biased sampling using RDS-based estimators. Sampling of the targeted 200 recruits per city was achieved rapidly (2 months in Tijuana, 2 weeks in Cd. Juárez). After excluding seeds and missing data, the sample prevalence of HCV, HIV and syphilis were 96.6, 1.9 and 13.5% respectively in Tijuana, and 95.3, 4.1, and 2.7% respectively in Cd. Juárez (where HBV prevalence was 84.7%). Syphilis cases were clustered in recruitment trees. RDS-corrected estimates of syphilis antibody prevalence ranged from 12.8 to 26.8% in Tijuana and from 2.9 to 15.6% in Ciudad Juárez, depending on how recruitment patterns were modeled, and assumptions about how network size affected an individual's probability of being included in the sample. RDS was an effective method to rapidly recruit IDUs in these cities. Although the frequency of HIV was low, syphilis prevalence was high, particularly in Tijuana. RDS-corrected estimates of syphilis prevalence were sensitive to model assumptions, suggesting that further validation of RDS is necessary.

Adolescent↗

PubMed2001

Economic analysis of randomized, controlled trials.

To facilitate the comparison of different treatment strategies, measures have been developed that bring together clinical, quality-of-life, and economic outcomes into summary measures such as the quality-adjusted life year, cost-effectiveness, and cost-utility ratios. A number of different types of economic evaluations have been developed, including cost-minimization, cost-effectiveness, and cost-utility analyses. Performance of economic analyses in association with randomized, controlled trials (RCT) has gained increasing enthusiasm in recent years. However, economic measures in RCTs are often outcomes of secondary interest and associated with frequent missing data and inadequate sample size. Variability in the cost measures used and the lack of agreement on clinically meaningful cost differences further limit the conclusions derived from such studies. Economic analyses should be limited to large trials with important trade-offs between efficacy and cost. The strengths and limitations of such analyses are discussed, and guidelines are offered for proper economic analyses in randomized, controlled trials.

Costs and Cost Analysis↗

PubMed1994

Improved body weight status as a result of nutrition intervention in adult, HIV-positive outpatients.

OBJECTIVE: Malnutrition is an important consequence of infection with the human immunodeficiency virus (HIV); involuntary weight loss greater than 10% is one criterion that the Centers for Disease Control and Prevention uses for the diagnosis of acquired immunodeficiency syndrome (AIDS). This study was designed to determine whether nutrition intervention in a group of adult, HIV-positive outpatients affected weight maintenance. METHODS: We undertook a retrospective review of 175 patient charts from the AIDS Reproductive Health Clinic and the Center for Special Studies at The New York Hospital. Forty-nine charts were excluded because the patient expressed a desire to reduce weight, discontinued medical care, or died. Seven charts were eliminated because of missing data. In the remaining patients (n = 119), weights were recorded for the initial clinic contact and for a follow-up visit at least 6 months later. Nutrition intervention completed by a registered dietitian was indicated on 42 patient charts (intervention group); intervention included dietary assessment, intake analysis, appropriate counselling, follow-up, and provision of supplements as needed. The remaining 77 charts did not indicate nutrition intervention; this group was called the nonintervention group. Differences between the intervention and nonintervention groups were analyzed using the two-tailed Fisher exact test and the Mann-Whitney nonparametric test. RESULTS: Forty-two subjects (35% of the total) recieved nutrition intervention, including all of those with gastrointestinal problems (n = 10) and wasting (n = 11). Individuals in the intervention group gained a significant (P < .02) 1.2 +/- 11.4 lb (mean +/- standard deviation; median = +3 lb) compared with those in the nonintervention group who lost a mean of 3.5 +/- 12.8 lb (median = -4 lb). Twenty-six subjects (63%) in the intervention group maintained or gained weight compared with 32 subjects (42%), in the nonintervention group. CONCLUSION: The results of this study suggest that nutrition intervention in HIV-infected persons can improve nutritional status and may lead to an enhanced ability to fight infection.

Adult↗

PubMedDate not supplied

Correlates of dissociative symptomatology in patients with physical and sexual abuse histories.

Recent studies have demonstrated a high prevalence of sexual and physical abuse histories and high levels of dissociative symptoms in psychiatric inpatients. We examined whether severity, frequency, and age of onset of abuse correlated with subjects' levels of dissociative symptoms. Sixty-four women reporting a lifetime history of physical and/or sexual abuse were recruited from consecutive admissions to three wards of a psychiatric hospital. Subjects completed the Life Experiences Questionnaire (LEQ) and the Dissociative Experiences Scale (DES). Subjects' self-reports of severity, frequency, and age of onset of abuse were analyzed for correlations with DES score. More invasive sexual abuse was associated with more dissociation. Higher-frequency physical abuse was associated with more dissociation, but no conclusion could be drawn about the impact of frequent sexual abuse due to missing data. An inverse correlation was found between age of onset of abuse and degree of dissociative symptomatology. These preliminary findings are consistent with hypotheses linking more severe, more chronic, and earlier abuse to the greater development of dissociative symptoms. The findings further emphasize the importance of recognizing dissociative symptoms in the clinical setting, and of continued study into the effects of childhood trauma.

Adolescent↗

PubMedDate not supplied

A computer program for selection of variables in diagnostic and prognostic problems.

The computer program INDEP-SELECT has been developed for selection of an optimal subset from a set of possibly informative diagnostic or prognostic variables. But the program is equally useful for other discriminant analysis or pattern recognition problems involving variable selection. The approach is probabilistic; i.e., diagnostic probabilities are assigned to a patient on the basis of the values observed on the diagnostic variables. The statistical model used is largely based on the assumption of independency between the variables, but one model-parameter, the so-called 'global association factor', is added in order to take dependency into account. The stepwise forward selection strategy of adding in each selection step a new variable to the set of already selected variables, is used. The user may choose between a number of selection criteria. Such a criterion is used in order to decide in each selection step which variable should be added. All criteria are based on measures of diagnostic or prognostic performance. INDEP-SELECT is able to handle a large number of variables, also with missing data, and a large number of patients. The program is written in ANS Standard FORTRAN, and takes relatively little computation time.

Bayes Theorem↗

PubMed1994

A PC program for computing confidence bands for average and individual growth curves.

Dawson et al. (Am. J. Med. Genet. 7, 529-536, 1980) developed a procedure for constructing confidence bands for both average and individual growth curves which may be of considerable value in the study of growth and development. This paper describes their method for constructing, and provides a menu-driven GAUSS386i program for computing these confidence bands. It is demonstrated how these bands are useful for both the diagnosis and prognostication of growth patterns with known levels of confidence. It is assumed that the study is planned so that individuals will be measured at the same times, but missing data are allowed.

Confidence Intervals↗

PubMed1994

Implementation of exact and approximate randomization tests for polynomial growth curves.

Two stand-alone, menu-driven PC programs, written in GAUSS386i, which compare groups of growth curves in a completely randomized design using either (a) exact or (b) approximate randomization tests, are described, illustrated, and made available to interested readers. The programs accommodate missing data in the context of studies planned to have common times of measurement, but where some of the measurement sequences are incomplete. The measurement whose growth is being monitored need not have a Gaussian distribution. We consider the hypothesis that the mean growth curves in G groups are the same; and either compute the exact P value (exact test), or estimate, and provide a confidence interval for, the P value (approximate test).

Algorithms↗

PubMed1994

Extension of the Carter-Yang polynomial growth curve model to allow unique times of measurement for subjects.

A PC program extending the procedure due to Carter and Yang (Commun Stat: Theory Methods, 8 (1986) 2507-2526) to allow unique times of measurement for subjects is described, illustrated and made available. Given longitudinal observations on each of N subjects comprising a single group, this program determines the lowest degree polynomial in time adequate to fit the average growth curve (AGC); estimates this curve and provides confidence bands for the AGC, and confidence intervals for the corresponding polynomial regression coefficients; and so-called prediction intervals which, with a given level of confidence, will contain the growth curve of a 'new' subject from the same population of which the N subjects constitute a random sample. Two kinds of missing data are accommodated. First, in the context of studies planned so that subjects will be measured at identical times and, second, in unstructured studies where subjects may present with their own, unique times of measurement.

Body Height↗

PubMed1991

Decision making in dentistry. Part I: A historical and methodological overview.

The study of clinical decision making provides a common model on which to base dental practice and thus promotes standardization of care and treatment. Decision analysis can assist in identifying missing data in clinical problems and thus generate clinically relevant research agendas. In Part I of this article several of the leading methods of decision analysis are briefly described with examples of how they can be applied in dentistry. The methods presented are Bayes' theorem, decision-tree design, receiver-operating-characteristic curves, sensitivity analysis, and utilities assessment.

Decision Making↗

PubMed1991

Decision making in dentistry. Part II: Clinical applications of decision methods.

The study of clinical decision making provides a common model on which to base dental practice and thus promotes standardization of care and treatment. Decision analysis can assist in identifying missing data in clinical problems and thus generate clinically relevant research agendas. Part II reviews the current literature focusing on three areas of decision making in dentistry: diagnosis, treatment planning, and disease prediction. The growing body of literature indicates that wide variation exists among the treatment plans made by dentists. Considerable bias arises from many sources of uncertainty in decision making, including the limitations of human memory and judgment. Literature pertaining to computer application of decision analysis in dentistry and to policy making are reviewed.

Decision Making↗

PubMed1992

Mood and global functioning in borderline personality disorder: individual regression models for longitudinal measurements.

This report addresses the need for prospective studies of personality disorders, as well as some of the difficulties encountered in longitudinal studies when missing data occur due to subject attrition and variable follow-up intervals. Various statistical methods for handling repeated measurements data are reviewed. Many of these methods are quite complex and require expert statistical skills. A simpler way to handle multivariate data using single-number summary scores is proposed as an alternative which is efficient and more readily understood by professionals in many disciplines. Findings are presented from a prospective study of borderline personality disorder which utilized repeated observations over time. Individual regression models were applied to each subject's repeated measurements to obtain a summary of his or her trend on measures of mood and global functioning. The individual regressions produced separate statistics, slopes summarizing rates of change and intercepts which estimated initial levels of functioning. These summaries were then used in group analyses. Findings indicated that subjects showed mild to moderate impairment in mood and moderate impairment in overall functioning. The individual slopes indicated that little overall change was observed during the 5-year period after initial assessment. Neither presence of borderline diagnosis (definite vs. trait vs. no borderline diagnosis) nor gender predicted initial levels of functioning or rates of change. Further examination of other predictors which may influence longterm outcome, such as history of childhood trauma or presence of schizotypal personality features, is suggested. It is concluded that prospective studies are essential in establishing the validity of personality disorders and in understanding individual variation in outcomes.

Adaptation, Psychological↗