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PubMed2004

Multiple-stage screening and mortality in the Multiple Risk Factor Intervention Trial.

BACKGROUND: During the design phase of a clinical trial, sample size estimates should take into account medical screening criteria, the 'healthy volunteer' effect, consequences of run-in phases, and secular trends in the event rate of interest. All of these have been shown to relate to subsequent event rates, and hence trial power to detect intervention effects. The Multiple Risk Factor Intervention Trial (MRFIT) used three successive screenings of 361 662 men to enroll 12 866; observed coronary heart disease (CHD) mortality after a mean of 6.9 years was substantially lower than projected during design. We explore factors which may have contributed to these mortality differences and whether they persisted throughout follow-up. METHODS: Proportional hazards models were used to compare 25-year mortality according to trial eligibility, self-exclusions, medical exclusions, and participation. RESULTS: After adjustment for baseline risk factors and age, there was higher mortality among men excluded for presence of disease [hazard ratio (HR) 1.52, 95% confidence interval (CI) 1.43-1.61, for total; HR 1.92, CI 1.75-2.11, for CHD] compared to those not excluded which persisted throughout follow-up. Volunteers had lower total (HR 0.82, CI 0.76-0.87) and CHD (HR 0.79, CI 0.70-0.88) mortality than those discontinuing participation. Men excluded with characteristics deemed likely to interfere with adherence had higher total (HR 1.19, CI 1.07-1.33) and non-cardiovascular disease (CVD) (HR 1.32, CI 1.14-1.53) mortality but no higher CVD (HR 1.04, CI 0.88-1.23) or CHD (HR 0.98, CI 0.80-1.20) mortality compared to those not excluded. Differences in mortality were stronger during the first five years, but declined only slightly over 25 years. CONCLUSIONS: 25-year mortality was significantly higher for non-volunteers and exclusions. Differences between observed and predicted six-year total mortality for trial participants were largely attributable to volunteers and exclusions, but there were additional differences for CHD mortality, which were likely due to downward secular trends. These results emphasize the importance of anticipating these factors during clinical trial design, even for trials of short duration.

Adult↗
PubMed2005

Minority recruitment to the Selenium and Vitamin E Cancer Prevention Trial (SELECT).

BACKGROUND: Previous large chemoprevention studies have not recruited significant numbers of minorities. The Selenium and Vitamin E Cancer Prevention Trial (SELECT) is a large phase III study evaluating the impact of selenium and vitamin E on the clinical incidence of prostate cancer. Over 400 SELECT study sites in the USA, Canada, and Puerto Rico recruited men to this trial. The SELECT recruitment goal was 24% minorities, with 20% black, 3% Hispanic, and 1% Asian participants. The goal for black participants was set at 20% because of their proportion in the United States population and their prevalence of prostate cancer. METHODS: The minority recruitment strategies in SELECT were to: 1) consider minority recruitment during site selection; 2) expand the eligibility criteria by lowering the age criterion for black men and including men with controlled co-morbid illnesses; 3) develop a national infrastructure; 4) give additional funds to sites with the potential to increase black enrollment; and 5) provide resources to maximize free media opportunities to promote SELECT. RESULTS: SELECT recruitment began in August 2001 and was intended to last five years, but concluded two years ahead of schedule in June 2004. Of the 35 534 participants enrolled, 21% were minorities, with 15% black, 5% Hispanic, and 1% Asian. CONCLUSIONS: Careful planning, recruitment of large numbers of clinical centers and adequate resources accomplished by the combined efforts of the National Cancer Institute (NCI), Southwest Oncology Group (SWOG), SELECT Recruitment and Adherence Committee (RAC), SELECT Minority and Medically Underserved Subcommittee (MMUS), and the local SELECT sites resulted in attainment of the estimated sample size ahead of schedule and recruitment of the largest percentage of black participants ever randomized to a cancer prevention trial.

Black or African American↗
PubMed2000

Gemcitabine plus vinorelbine versus vinorelbine alone in elderly patients with advanced non-small-cell lung cancer.

PURPOSE: To evaluate whether the addition of gemcitabine (G) to vinorelbine (V) improves survival and quality of life (QoL) among elderly patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with NSCLC aged >/= 70 years with advanced disease were randomly allocated to receive V 30 mg/m(2) on days 1 and 8 every 3 weeks or G 1,200 mg/m(2) + V 30 mg/m(2) on days 1 and 8 every 3 weeks. The estimated sample size was 120 patients per arm, but an interim analysis of survival was planned based on the first 60 patients per arm. RESULTS: In May 1999, the survival data were analyzed of 120 eligible patients (V group = 60; G + V group = 60) who had been randomized from June 1997 to February 1999. Forty-nine patients had stage IIIB disease, and 71 had stage IV. At a median potential follow-up of 14 months (range, 3 to 22 months), 93 patients had died (G + V group = 41; V group = 52). In the G + V group, median survival time was 29 weeks and projected 1-year survival was 30%; these values were 18 weeks and 13% in the V group. According to multivariate Cox analysis, the risk of death in the G + V arm compared with the V arm was 0.48 (95% confidence interval, 0. 29 to 0.79; P <.01). Combination therapy was also associated with a clear delay in symptom and QoL deterioration. The overall response rates were 22% and 15% in the G + V and V groups, respectively. CONCLUSION: In elderly patients with NSCLC, G + V treatment is associated with significantly better survival than is V alone.

Aged↗
PubMed2003

Radiotherapy patterns of care study in lung carcinoma.

PURPOSE: For the first time, a lung Patterns of Care Study was conducted to determine the national patterns of radiation (RT) practice in patients treated for nonmetastatic lung cancer in 1998 to 1999. MATERIALS AND METHODS: A national survey of randomly selected RT institutions in the United States was conducted using two-stage cluster sampling, stratified by practice type. Patients with nonmetastatic lung cancer (Karnofsky performance score [KPS] > or = 60), who received RT as definitive or adjuvant therapy, were randomly selected. To determine national estimates, sample size was weighted by the relative number of institutions per strata and the number of patient records reviewed per the number of patients eligible. Accordingly, 42,335 patient records from 58 institutions were reviewed by trained research associates. The unweighted sample size (or number of patients) was 541. RESULTS: The histologies were small-cell lung cancer (SCLC) in 14.5% of patients versus non-small-cell lung cancer (NSCLC) in 85.5% of patients. The median age was 67 years (range, 29 to 92 years); 61% of patients were male, and 38% were current smokers. Bone scans and brain imaging were not obtained in 34% and 52% of clinical stage (CS) III NSCLC patients, respectively. Regarding treatment strategies, for SCLC and CS III NSCLC, chemotherapy plus RT was used significantly more than RT alone (P <.05); in CS I NSCLC, RT alone was the primary treatment (P <.05). Overall, 58% of patients received systemic therapy. On multivariate analysis, factors correlating with increased use of chemotherapy included younger age, histology (SCLC > NSCLC), increasing CS, increasing KPS, and lack of comorbidities. Only 3% of all patients were treated on prospective clinical trials. CONCLUSION: This study establishes the general patterns of care for lung carcinoma in RT facilities within the United States. As supported by clinical trials, patients with limited-stage SCLC and CS III NSCLC received chemotherapy plus RT more than they received RT alone. Further improvements in staging, smoking cessation, and increased accrual to clinical trials must be encouraged.

Adult↗
PubMed2004

Comparison of different MRI brain atrophy rate measures with clinical disease progression in AD.

OBJECTIVE: To correlate different methods of measuring rates of brain atrophy from serial MRI with corresponding clinical change in normal elderly subjects, patients with mild cognitive impairment (MCI), and patients with probable Alzheimer disease (AD). METHODS: One hundred sixty subjects were recruited from the Mayo Clinic Alzheimer's Disease Research Center and Alzheimer's Disease Patient Registry Studies. At baseline, 55 subjects were cognitively normal, 41 met criteria for MCI, and 64 met criteria for AD. Each subject underwent an MRI examination of the brain at the time of the baseline clinical assessment and then again at the time of a follow-up clinical assessment, 1 to 5 years later. The annualized changes in volume of four structures were measured from the serial MRI studies: hippocampus, entorhinal cortex, whole brain, and ventricle. Rates of change on several cognitive tests/rating scales were also assessed. Subjects who were classified as normal or MCI at baseline could either remain stable or convert to a lower-functioning group. AD subjects were dichotomized into slow vs fast progressors. RESULTS: All four atrophy rates were greater among normal subjects who converted to MCI or AD than among those who remained stable, greater among MCI subjects who converted to AD than among those who remained stable, and greater among fast than slow AD progressors. In general, atrophy on MRI was detected more consistently than decline on specific cognitive tests/rating scales. With one exception, no differences were found among the four MRI rate measures in the strength of the correlation with clinical deterioration at different stages of the disease. CONCLUSIONS: These data support the use of rates of change from serial MRI studies in addition to standard clinical/psychometric measures as surrogate markers of disease progression in AD. Estimated sample sizes required to power a therapeutic trial in MCI were an order of magnitude less for MRI than for change measures based on cognitive tests/rating scales.

Aged↗
PubMed2006

Brain volume changes in CADASIL: a serial MRI study in pure subcortical ischemic vascular disease.

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small vessel disease causing stroke and subcortical vascular dementia. Recent studies in sporadic subcortical ischemic vascular disease have drawn attention to brain atrophy as a clinically important marker of disease progression. However, little is known about the role of brain atrophy and its clinical correlates in CADASIL. METHOD: The authors determined the normalized brain volume (NBV) and percent brain volume change (PBVC) over 2 years in 76 CADASIL subjects (45.1 +/- 9.7 years) using the SIENA (structural image evaluation using normalization of atrophy) software and its adaptation for cross-sectional measurements (SIENAX). Baseline assessments included systolic blood pressure (SBP), homocysteine levels, BMI, and APOE genotyping. T2-lesion volumes and clinical scales were assessed at both time points. RESULTS: The NBV significantly correlated with all clinical scores (Rankin, NIH Stroke Scale, Barthel, structured interview for the diagnosis of Alzheimer dementia and multi-infarct dementia, Mattis dementia rating scale) at both time points independently of age and sex. PBVC correlated with changes of all clinical scores (all p < 0.01) except for the Mattis dementia rating scale (p = 0.10). In a linear regression model, age (p < 0.001), male sex (p < 0.01), and SBP (p = 0.07) were the main risk factors for a lower NBV at baseline. Age (p < 0.001) and SBP (p = 0.01) were risk factors for brain volume loss during follow-up. Sample size estimates showed that the number of individuals needed to demonstrate a treatment effect in a trial can be reduced when PBVC is used as an endpoint. CONCLUSIONS: This study identifies brain atrophy as an important aspect of the disease process in CADASIL and establishes significant correlations with multiple clinical aspects including cognition. Age and systolic blood pressure are risk factors for brain volume loss during follow-up. Percent brain volume change seems promising as an adjunct outcome measure in future interventional trials.

Adult↗
PubMed2005

Measurement and choice of drinking outcome variables in the COMBINE Study.

OBJECTIVE: The COMBINE Study, a federally funded multisite clinical trial, endeavored to choose drinking and related outcome variables that were scientifically sound and had both convergent validity with previously published studies and face validity for clinical meaning. This article describes these variables and the methods used to collect them. METHOD: In choosing the primary outcome drinking variables, the mechanisms of action of naltrexone and acamprosate were considered along with previously published results for them and the psychosocial therapies utilized (Project MATCH). In addition, enough previous data were required to abstract meaningful power calculations for sample size estimates. Attention was paid to methodological detail in collection of drinking data, and confirmatory biological variables (carbohydrate deficient transferrin and gamma glutamyl transpeptidase) were incorporated into the study design. RESULTS: Daily standard drinks were collected by calendar-based methods with a stated goal of 90% within-treatment drinking data to be collected. "Percentage of days abstinent" and "time to first heavy drinking day" were chosen as primary outcome variables. Standardized daily alcohol consumption data can be applied to various statistical approaches, including hierarchical linear modeling and multiple relapse event analyses, which can evaluate a progression of improvement or worsening over time. CONCLUSIONS: Trained individuals using calendar-based methods attempting to collect all daily drinking data, independent of treatment dropout, should enhance interpretive validity of treatment differences. Convergence of drinking data with biological marker changes, quality of life, craving and health services utilization will enhance the overall validity of both the within-treatment and the posttreatment results for the COMBINE Study.

Alcoholism↗
PubMedDate not supplied

Comparison of blood pressure measurement consistency using tonometric and automated oscillometric instruments.

To effectively evaluate treatments for hypertension, researchers and clinicians must be able to measure blood pressure (BP) in a valid and reliable way. The purpose of this study is to compare measurements made in the clinic using beat-to-beat radial BP tonometry, measurements made during 24 hours using an ambulatory BP monitor, and measurements made in the clinic using an automated oscillometric BP monitor. Fifty-seven adults with primary hypertension participated in this study, which used a repeated measures descriptive design. Clinic and ABPM daytime averages were compatible for both SBP and DBP. In contrast, clinic SBP was 7.56 mmHg higher than the beat-to-beat SBP; clinic DBP was 9.83 mmHg higher than the beat-to-beat DBP. These data suggest that automated clinic measurements may be used in place of daytime ambulatory BP measurements. We also estimate sample sizes for future studies based on characteristics of clinic BP.

Adult↗
PubMed1999

Methodological hurdles in conducting pharmacoeconomic analyses.

As total healthcare spending increases throughout the world, greater emphasis is being placed on research which demonstrates value for medical interventions, including new and existing pharmaceuticals. Pharmacoeconomic evaluations can assist manufacturers, insurers, clinicians, governmental agencies, policy-makers and consumers to make informed, appropriate decisions about adoption and application of new medications. Because of the far-reaching implications of this research, it is important that researchers adequately address methodological challenges. In this article, we describe the uses of results of pharmacoeconomic trials, identify and discuss various study designs and methods for gathering nonclinical outcome data which may differ significantly from clinical outcome data, and consider the importance and difficulty of incorporating the patients' experience into such trials. Researchers in this area must give specific consideration to sample size estimation for economic outcomes, and carefully handle time issues including duration of observation for complications and discounting of future health and financial consequences. Costs from different perspectives associated with resource use should be assembled in a standard fashion. Use of charges which may not be standardised across geographical or organisational boundaries are discouraged. Inclusion of appropriate health-related quality-of-life (HR-QOL) and utility instruments is increasingly important, but controversy over the best methods still exists. While there is little question of the importance of pharmacoeconomic evaluations, they are expensive. Well designed and executed pharmacoeconomic trials can justify this expense by helping decision-makers understand which treatments have value.

Economics, Pharmaceutical↗
PubMed1982

Retinopathy in juvenile-onset type I diabetes of short duration.

We evaluated the prevalence and severity of diabetic retinopathy in 173 juvenile-onset, type I diabetic subjects and 78 nondiabetic controls of similar age, race, and sex distribution by stereoscopic fundus photography and fluorescein angiography, performed by a standardized protocol and evaluated by five expert, masked observers. The overall prevalence of retinopathy was 18% in the diabetic group and 0% in the controls. Retinopathy prevalence increased with duration of diabetes in the diabetic group, with a prevalence of 1% from 0--4 yr after diagnosis, 25% after 5--9 yr, and 67% 10--16 yr after onset of the systemic disease. There was an independent association with age, with little retinopathy before age 15 and a 48% prevalence in older persons. Retinopathy was also found to be independently associated with the following: diabetic "control," evaluated semiquantitatively but on a masked basis; lens opacities; and frequency of daily insulin injections. Among the 166 diabetic subjects who had both angiography and photography, a retinopathy prevalence of 17% was detected by angiography and 11% by photography. This difference was statistically significant (P = 0.01). This study provides baseline data for use in estimating sample size in controlled trials of therapeutic measures to prevent retinopathy in juvenile diabetic populations. The study also supports the hypothesis that long-term hyperglycemia as well as changes (possibly hormonal in nature) associated with puberty are causally related to diabetic retinopathy.

Adolescent↗
PubMed1991

Design and organization of the herpetic eye disease study (HEDS).

The Herpetic Eye Disease Study (HEDS) includes three double-masked, placebo-controlled clinical trials for potentially blinding herpes simplex virus (HSV) eye infections. One study compares a tapering dosage of topical prednisolone or placebo eye drops for HSV stromal keratitis (HEDS-SKN). Two other trials compare oral acyclovir to placebo capsules for HSV stromal keratitis (HEDS-SKS) or iridocyclitis (HEDS-IRT) in patients on a tapering dosage of topical prednisolone drops. All medications are administered for 10 weeks. Outcome is judged by time to recurrent disease or treatment failure. This paper presents the design, estimated sample size and recruitment as of July 25, 1990.

Acyclovir↗
PubMed1996

Controlled clinical trials in cancer research.

Knowledge of important aspects of the design and analysis of clinical trials is essential to clinical researchers and readers of medical literature. A brief description of proper trial design, including the contents of a trial protocol, as well as different strategies to avoid bias, is given. The concept of p-values is explained, and some commonly used statistical analysis methods are mentioned. Statistical power is defined, and two useful formulas and examples of estimating sample size are presented. The correct interpretation of trial results is emphasized, and misinterpretations and errors that frequently occur are dealt with. Various issues regarding multiple significance testing, such as interim analyses, multiple endpoints, and subgroup analyses, are addressed.

Controlled Clinical Trials as Topic↗
PubMed2006

Translating clinical research into clinical practice: impact of using prediction rules to make decisions.

Clinical prediction rules, sometimes called clinical decision rules, have proliferated in recent years. However, very few have undergone formal impact analysis, the standard of evidence to assess their impact on patient care. Without impact analysis, clinicians cannot know whether using a prediction rule will be beneficial or harmful. This paper reviews standards of evidence for developing and evaluating prediction rules; important differences between prediction rules and decision rules; how to assess the potential clinical impact of a prediction rule before translating it into a decision rule; methodologic issues critical to successful impact analysis, including defining outcome measures and estimating sample size; the importance of close collaboration between clinical investigators and practicing clinicians before, during, and after impact analysis; and the need to measure both efficacy and effectiveness when analyzing a decision rule's clinical impact. These considerations should inform future development, evaluation, and use of all clinical prediction or decision rules.

Biomedical Research↗
PubMed2001

Physician assisted suicide perceptions among patients presenting to family physicians at a teaching hospital in Karachi, Pakistan.

OBJECTIVE: To study the perceptions on physician assisted suicide, among patients presenting to family physicians, at a teaching hospital in Karachi, Pakistan. METHOD: The study was carried out at the Community Health Center of The Aga Khan University Hospital, Karachi, between December 1999 and May 2000. The principal and co-investigators filled a pre-coded and pretested questionnaire consisting of important demographic characteristics and bio-medical ethics issues. A system of convenience sampling was used and a written consent was taken from respondents over the age of 16 years, who agreed to participate. The data were managed by using the Epi Info (version 6.0) program. RESULTS: Four hundred twenty respondents were interviewed against an estimated sample size of 385. Majority (88%) were males between 25 and 34 years of age, and were self employed or in private service. Overall 9% respondents were advocated of physician assisted suicide, advocates was 9%. Those who advocated the Physician assisted suicide were more likely to be female, elderly, married and educated amongst the total respondents. Those who support Physician assisted suicide were less likely to attach divine qualities to physicians and were more bold, courageous and tolerant towards broader biomedical ethics issues. CONCLUSION: We have found a substantial acceptability to the idea of Physician assisted suicide in a Muslim society and have identified characteristics of those who support it.

Adult↗
PubMedDate not supplied

[Arterial hypertension in Mexico: results of the National Health Survey 2000].

AIMS: Hypertension remains as a major cause of cardiovascular morbidity in México. The Health National Survey 2000 of México was performed to analyze the current status of the prevalence of some risk factors such as diabetes, hypertension (HTA), obesity, smoking, and proteinuria. METHODS: A National Survey was carried out in México where 45,300 individuals between 20 to 69-y.o. were screened. The estimated sample size was calculated considering the total number of persons into the mentioned age; a minimal prevalence of 6% of the included risk factors, at a significance level of 0.05; a maximum relative error of 0.145, and a rate of response of at least 70%. Diagnosis of HTA was accepted in: previous medical diagnosis with prescription of antihypertensive drugs, or high blood pressure (> or = 140/90 mmHg) detected during the interview. Data were adjusted for the national distribution of age-groups and gender (established in 2000, INEGI). RESULTS: 38,377 (98.8%) individuals were correctly screened for blood pressure. The prevalence of hypertension in México was 30.05% (34.2% in men and 26.3% in women). The prevalence was directly related with age and gender. The percentage of mexicans with HTA after 50-y.o. is > 50%. The prevalence was greater in women after 50-y.o. Among persons with hypertension, treatment was detected in 46% and approximately 20% of them were controlled (< 140/90 mmHg). The percentage of mexicans with HTA who were unaware that they have high blood pressure was 61%. The total percentage of HTA controlled was 14.6%. The North states had the greater prevalence (approximately 34%) of HTA while South states had the lower prevalence (27%). The odds ratio (age/sex-adjusted) for HTA were: for diabetes 1.54(CI95%, 1.44-1.63); for obesity 2.3 (CI 95%, 2.22-2.43); for smoking 1.26 (CI 95%, 1.21-1.32). For proteinuria subjects, 40% had HTA. CONCLUSIONS: Around 15 millions of mexicans between 20 to 69-y.o. had hypertension, 60% of them are unaware. The prevalence of hypertension in México (30.05%) has increased. Among persons with hypertension -15% are controlled. The North of México has the higher prevalence of hypertension. Diabetes, smoking, and obesity increase the risk of hypertension. The 2000 National Survey of Health shows the epidemiological trend in several important chronic diseases in México and declare an urgent need of new strategies for detection, control and treatment of hypertension.

Adult↗
PubMed2003

Pilot clinical trial of intravenous doxycycline versus placebo for rheumatoid arthritis.

OBJECTIVE: To screen for potential efficacy and assess the feasibility of intravenous (IV) doxycycline as a treatment for rheumatoid arthritis (RA). METHODS: The study was a (stratified, block) randomized, double blind, 12 week, pilot trial of IV doxycycline 300 mg/day versus identical appearing IV placebo given over 2 h for 14 days. The primary comparison was to a hypothesized placebo rate of 20% as described by Paulus. If a total of 14 consecutive subjects receiving doxycycline treatment did not respond, it would be considered futile to proceed to a Phase III trial. We planned a placebo group of 14 subjects to verify the placebo response rate and estimate sample size required for a definitive Phase III trial, if such a trial was warranted based on the pilot study. American College of Rheumatology (ACR) RA response criteria were used. After 23 subjects entered, the study was closed due to recruitment difficulties. RESULTS: At baseline, mean (SD) tender joint count was 37 (11.9), swollen joint count 30 (9.6), morning stiffness 317 (319) min, and erythrocyte sedimentation rate 72 mm/h (27.5). Randomization resulted in 10 subjects receiving doxycycline and 13 receiving placebo. Treatment was stopped in 8 subjects: in 6, treatment was ineffective (one taking doxycycline, 5 placebo), and in 2, rashes occurred (one taking doxycycline, one placebo). Only one subject met ACR response criteria in the doxycycline group and none in the placebo group. Having no responders in the placebo group was consistent with placebo response rate of 20% or less. Several patients required peripherally inserted central catheters for venous access. CONCLUSION: The efficacy of IV doxycycline as a treatment for RA could not be ruled out. However, as the proportion of responders was small, it is unlikely that potential efficacy of IV doxycycline would outweigh potential disadvantages of IV administration.

Adult↗
PubMed2002

Pulsed magnetic field therapy for osteoarthritis of the knee--a double-blind sham-controlled trial.

BACKGROUND AND METHODS: Pulsed magnetic field therapy is frequently used to treat the symptoms of osteoarthritis, although its efficacy has not been proven. We conducted a randomized, double-blind comparison of pulsed magnetic field and sham therapy in patients with symptomatic osteoarthritis of the knee. Patients were assigned to receive 84 sessions, each with a duration of 30 minutes, of either pulsed magnetic field or sham treatment. Patients administered the treatment on their own at home, twice a day for six weeks. RESULTS: According to a sample size estimation, 36 consecutive patients were enrolled. 34 patients completed the study, two of whom had to be excluded from the statistical analysis, as they had not applied the PMF sufficiently. Thus, 15 verum and 17 sham-treated patients were enrolled in the statistical analysis. After six weeks of treatment the WOMAC Osteoarthritis Index was reduced in the pulsed magnetic field-group from 84.1 (+/- 45.1) to 49.7 (+/- 31.6), and from 73.7 (+/- 43.3) to 66.9 (+/- 52.9) in the sham-treated group (p = 0.03). The following secondary parameters improved in the pulsed magnetic field group more than they did in the sham group: gait speed at fast walking [+6.0 meters per minute (1.6 to 10.4) vs. -3.2 (-8.5 to 2.2)], stride length at fast walking [+6.9 cm (0.2 to 13.7) vs. -2.9 (-8.8 to 2.9)], and acceleration time in the isokinetic dynamometry strength tests [-7.0% (-15.2 to 1.3) vs. 10.1% (-0.3 to 20.6)]. CONCLUSION: In patients with symptomatic osteoarthritis of the knee, PMF treatment can reduce impairment in activities of daily life and improve knee function.

Aged↗
PubMed2002

[Analysis of randomized controlled trials on otorhinolaryngological diseases in China].

OBJECTIVE: To evaluate the quality of randomized controlled trials (RCT) in otorhinolaryngology in China and offer evidence for the improvement of RCT. METHODS: Five kinds of Chinese journals of clinical otorhinolaryngology were searched, and RCTs were identified and analyzed according to the standards of Evidence Based Medicine. RESULTS: Two hundred and eighty seven issues were referred to, and eighty-one RCTs were finally identified and analyzed. Of these RCTs, 34.57% (28/81) had definite diagnostic standards, 38.27% (31/81) had including standards and 33.33% (27/81) had excluding standards; only 1.23% (1/81) got the approval of the participants; 40.74% (33/81) had moderate sample size, 3.70% (3/81) had large sample size and non of them mentioned sample size estimation; 81.48% (66/81) didn't report the method of randomization and 38.27% (31/81) had baseline comparison; 18.52% (15/81) didn't define the control interventions and 8.64% (7/81) even didn't explicate the experimental intervention; 32.10% (26/81) used blank comparison; 86.42% (70/81) didn't use blindness; 37.04% (30/81) didn't mention the adverse effects; 23.46% (19/81) used accredited standards to evaluate the outcomes; 11.11% (9/81) mentioned the loss of following-up and only 1.23% (1/81) treated the loss with statistics methods. CONCLUSION: The quantity and quality of otorhinolaryngological RCTs couldn't meet the clinical need. More high quality RCTs are required to improve the level of prevention and cure of otorhinolaryngologic diseases.

China↗