Power and sample size determination for the group comparison of patient-reported outcomes using the Rasch model: impact of a misspecification of the parameters.

abstract：BACKGROUND:This paper focuses on measuring the efficiency and effectiveness of two diagramming methods employed in key informant interviews with clinicians and health care administrators. The two methods are 'participatory diagramming', where the respondent creates a diagram that assists in their communication of answe...

journal_title：BMC medical research methodology

authors： Umoquit MJ,Dobrow MJ,Lemieux-Charles L,Ritvo PG,Urbach DR,Wodchis WP

更新日期：2008-08-08 00:00:00

abstract：BACKGROUND:Systematic reviewers seek to comprehensively search for relevant studies and summarize these to present the most valid estimate of intervention effectiveness. The more resources searched, the higher the yield, and thus time and costs required to conduct a systematic review. While there is an abundance of evi...

journal_title：BMC medical research methodology

authors： Crumley ET,Wiebe N,Cramer K,Klassen TP,Hartling L

更新日期：2005-08-10 00:00:00

abstract：BACKGROUND:Various papers have addressed pros and cons of the stepped wedge cluster randomized trial design (SWD). However, some issues have not or only limitedly been addressed. Our aim was to provide a comprehensive overview of all merits and limitations of the SWD to assist researchers, reviewers and medical ethics ...

journal_title：BMC medical research methodology

authors： de Hoop E,van der Tweel I,van der Graaf R,Moons KG,van Delden JJ,Reitsma JB,Koffijberg H

更新日期：2015-10-30 00:00:00

abstract：BACKGROUND:We developed and validated an automated database case definition for diabetes in children and youth to facilitate pharmacoepidemiologic investigations of medications and the risk of diabetes. METHODS:The present study was part of an in-progress retrospective cohort study of antipsychotics and diabetes in Te...

journal_title：BMC medical research methodology

authors： Bobo WV,Cooper WO,Stein CM,Olfson M,Mounsey J,Daugherty J,Ray WA

更新日期：2012-08-24 00:00:00

abstract：BACKGROUND:Standard random-effects meta-analysis methods perform poorly when applied to few studies only. Such settings however are commonly encountered in practice. It is unclear, whether or to what extent small-sample-size behaviour can be improved by more sophisticated modeling. METHODS:We consider likelihood-based...

journal_title：BMC medical research methodology

authors： Seide SE,Röver C,Friede T

更新日期：2019-01-11 00:00:00

abstract：BACKGROUND:One of the biggest challenges for population health studies is the recruitment of participants. Questions that investigators have asked are "who volunteers for studies?" and "does recruitment method influence characteristics of the samples?" The purpose of this paper was to compare sample characteristics of ...

journal_title：BMC medical research methodology

authors： Leung BM,McDonald SW,Kaplan BJ,Giesbrecht GF,Tough SC

更新日期：2013-12-06 00:00:00

abstract：BACKGROUND:Although some nonparametric methods have been proposed in the literature to test for the equality of median survival times for censored data in medical research, in general they have inflated type I error rates, which make their use limited in practice, especially when the sample sizes are small. METHODS:In...

journal_title：BMC medical research methodology

authors： Chen Z,Zhang G

更新日期：2016-03-16 00:00:00

abstract：BACKGROUND:Most electronic search efforts directed at identifying primary studies for inclusion in systematic reviews rely on the optimal Boolean search features of search interfaces such as DIALOG and Ovid. Our objective is to test the ability of an Ultraseek search engine to rank MEDLINE records of the included studi...

journal_title：BMC medical research methodology

authors： Sampson M,Barrowman NJ,Moher D,Clifford TJ,Platt RW,Morrison A,Klassen TP,Zhang L

更新日期：2006-02-24 00:00:00

abstract：BACKGROUND:Estimating the incidence of medical conditions using claims data often requires constructing a prevalence period that predates an event of interest, for instance the diagnosis of cancer, to exclude those with pre-existing conditions from the incidence risk set. Those conditions missed during the prevalence p...

journal_title：BMC medical research methodology

authors： Griffiths RI,O'Malley CD,Herbert RJ,Danese MD

更新日期：2013-03-06 00:00:00

abstract：BACKGROUND:A recent paper found that terminal digits of statistical values in Nature deviated significantly from an equiprobable distribution, indicating errors or inconsistencies in rounding. This finding, as well as the discovery that a large percentage of p values were inconsistent with reported test statistics, led...

journal_title：BMC medical research methodology

authors： Jeng M

更新日期：2006-09-13 00:00:00

abstract：BACKGROUND:Defeat and entrapment have been shown to be of central relevance to the development of different disorders. However, it remains unclear whether they represent two distinct constructs or one overall latent variable. One reason for the unclarity is that traditional factor analytic techniques have trouble estim...

journal_title：BMC medical research methodology

authors： Forkmann T,Teismann T,Stenzel JS,Glaesmer H,de Beurs D

更新日期：2018-01-25 00:00:00

abstract：BACKGROUND:The Anglia Menorrhagia Education Study (AMES) is a randomized controlled trial testing the effectiveness of an education package applied to general practices. Binary data are available from two sources; general practitioner reported referrals to hospital, and referrals to hospital determined by independent a...

journal_title：BMC medical research methodology

authors： Nixon RM,Duffy SW,Fender GR

更新日期：2003-09-24 00:00:00

abstract：BACKGROUND:The choice between paper data collection methods and electronic data collection (EDC) methods has become a key question for clinical researchers. There remains a need to examine potential benefits, efficiencies, and innovations associated with an EDC system in a multi-center medical record review study. MET...

journal_title：BMC medical research methodology

authors： Thwin SS,Clough-Gorr KM,McCarty MC,Lash TL,Alford SH,Buist DS,Enger SM,Field TS,Frost F,Wei F,Silliman RA

更新日期：2007-06-18 00:00:00

abstract：BACKGROUND:The longitudinal birth cohort study is the preferred design for studies of childhood health, particularly atopic disease. Still, prospective data collection depends on recollection of the medical history since the previous visit representing a potential recall-bias. We aimed to ascertain the quality of infor...

journal_title：BMC medical research methodology

authors： Vissing NH,Jensen SM,Bisgaard H

更新日期：2012-10-22 00:00:00

abstract：BACKGROUND:The Community Reintegration of Service Members (CRIS) is a new measure of community reintegration developed to measure veteran's participation in life roles. It consists of three sub-scales: Extent of Participation (Extent), Perceived Limitations with Participation (Perceived), and Satisfaction with Particip...

journal_title：BMC medical research methodology

authors： Resnik LJ,Clark MA,Borgia M

更新日期：2011-06-25 00:00:00

abstract：BACKGROUND:It is widely recognised that the pursuit of sustainable development cannot be accomplished without addressing inequality, or observed differences between subgroups of a population. Monitoring health inequalities allows for the identification of health topics where major group differences exist, dimensions of...

journal_title：BMC medical research methodology

authors： Hosseinpoor AR,Nambiar D,Schlotheuber A,Reidpath D,Ross Z

更新日期：2016-10-19 00:00:00

abstract：:The quality of a consultation provided by a physician can have a profound impact on the quality of care and patient engagement in treatment decisions. When the COPD Assessment Test (CAT) was developed, one of its aims was to aid the communication between physician and patient about the impact of COPD. We developed a n...

journal_title：BMC medical research methodology

authors： Gruffydd-Jones K,Marsden H,Holmes S,Kardos P,Escamilla R,Dal Negro R,Roberts J,Nadeau G,Leather D,Jones P

更新日期：2013-05-10 00:00:00

abstract：BACKGROUND:Recruitment to clinical trials can be challenging. Methods that improve the efficiency of trial recruitment are needed to increase successful study completions. The aim of this study was to ascertain whether sending an audio-visual presentation on a digital versatile disc (DVD), along with usual study invita...

journal_title：BMC medical research methodology

authors： Rogers A,Flynn RWV,Mackenzie IS,MacDonald TM

更新日期：2019-01-30 00:00:00

abstract：BACKGROUND:In order to accurately measure and monitor levels of moderate-to-vigorous physical activity (MVPA) and sedentary behaviour (SB) in older adults, cost efficient and valid instruments are required. To date, the International Physical Activity Questionnaire (IPAQ) has not been validated with older adults (aged ...

journal_title：BMC medical research methodology

authors： Cleland C,Ferguson S,Ellis G,Hunter RF

更新日期：2018-12-22 00:00:00

abstract：BACKGROUND:The primary aim of this study was to provide an estimate of effect size for the functional outcome of operative versus non-operative treatment for patients with an acute rupture of the Achilles tendon using accelerated rehabilitation for both groups of patients. The secondary aim was to assess the use of a c...

journal_title：BMC medical research methodology

authors： Kearney RS,Achten J,Parsons NR,Costa ML

更新日期：2011-04-05 00:00:00

abstract：BACKGROUND:Studies have shown that industry-sponsored meta-analyses of drugs lack scientific rigour and have biased conclusions. However, these studies have been restricted to certain medical specialities. We compared all industry-supported meta-analyses of drug-drug comparisons with those without industry support. ME...

journal_title：BMC medical research methodology

authors： Jørgensen AW,Maric KL,Tendal B,Faurschou A,Gøtzsche PC

更新日期：2008-09-09 00:00:00

abstract：BACKGROUND:The intraclass correlation coefficient (ICC) is widely used in biomedical research to assess the reproducibility of measurements between raters, labs, technicians, or devices. For example, in an inter-rater reliability study, a high ICC value means that noise variability (between-raters and within-raters) is...

journal_title：BMC medical research methodology

authors： Ionan AC,Polley MY,McShane LM,Dobbin KK

更新日期：2014-11-22 00:00:00

abstract：BACKGROUND:The International Cancer Benchmarking Partnership aims to study international differences in cancer survival and the possible causes. Participating countries are Australia, Canada, Norway, Sweden, Denmark and the UK and a particular focus area is differences in awareness and beliefs about cancer. In this con...

journal_title：BMC medical research methodology

authors： Hvidberg L,Pedersen AF,Wulff CN,Carlsen AH,Vedsted P

更新日期：2017-04-26 00:00:00

abstract：BACKGROUND:Modern modelling techniques may potentially provide more accurate predictions of binary outcomes than classical techniques. We aimed to study the predictive performance of different modelling techniques in relation to the effective sample size ("data hungriness"). METHODS:We performed simulation studies bas...

journal_title：BMC medical research methodology

authors： van der Ploeg T,Austin PC,Steyerberg EW

更新日期：2014-12-22 00:00:00

abstract：BACKGROUND:The development of risk prediction models is of increasing importance in medical research - their use in practice, however, is rare. Among other reasons this might be due to the fact that thorough validation is often lacking. This study focuses on two Bayesian approaches of how to validate a prediction rule ...

journal_title：BMC medical research methodology

authors： Held U,Bové DS,Steurer J,Held L

更新日期：2012-07-20 00:00:00

abstract：BACKGROUND:Sero- prevalence studies often have a problem of missing data. Few studies report the proportion of missing data and even fewer describe the methods used to adjust the results for missing data. The objective of this review was to determine the analytical methods used for analysis in HIV surveys with missing ...

journal_title：BMC medical research methodology

authors： Mosha NR,Aluko OS,Todd J,Machekano R,Young T

更新日期：2020-03-14 00:00:00

abstract：BACKGROUND:Longitudinal studies using data collected as part of usual care risk providing biased results if visit times are related to the outcome of interest. Statistical methods for mitigating this bias are available but rarely used. This lack of use could be attributed to a lack of need or to a lack of awareness of ...

journal_title：BMC medical research methodology

authors： Farzanfar D,Abumuamar A,Kim J,Sirotich E,Wang Y,Pullenayegum E

更新日期：2017-09-06 00:00:00

abstract：BACKGROUND:The Health Care Module of the European Health Interview Survey (EHIS) is aimed to obtain comparable information on the use of inpatient and ambulatory care in all EU member states. In this study we assessed the validity of self-reported information on the use of health care, collected through this instrument...

journal_title：BMC medical research methodology

authors： Van der Heyden J,Charafeddine R,De Bacquer D,Tafforeau J,Van Herck K

更新日期：2016-08-16 00:00:00

abstract：BACKGROUND:Claims databases are generally considered inadequate for obesity research due to suboptimal capture of body mass index (BMI) measurements. This might not be true for bariatric surgery because of reimbursement requirements and changes in coding systems. We assessed the availability and validity of claims-base...

journal_title：BMC medical research methodology

authors： Li X,Lewis KH,Callaway K,Wharam JF,Toh S

更新日期：2020-09-07 00:00:00

abstract：BACKGROUND:Postal questionnaires are widely used to collect outcome data on participants. However, a poor response to questionnaires will reduce the statistical power of the study and may introduce bias. A meta analysis of ten trials offering study results, largely in the fields of education and marketing, was shown to...

journal_title：BMC medical research methodology

authors： Cockayne S,Torgerson DJ

更新日期：2005-10-26 00:00:00