abstract：BACKGROUND:Small number of clusters and large variation of cluster sizes commonly exist in cluster-randomized trials (CRTs) and are often the critical factors affecting the validity and efficiency of statistical analyses. F tests are commonly used in the generalized linear mixed model (GLMM) to test intervention effect...

journal_title：BMC medical research methodology

authors： Li P,Redden DT

更新日期：2015-04-23 00:00:00

abstract：BACKGROUND:Missing data are common in medical research, which can lead to a loss in statistical power and potentially biased results if not handled appropriately. Multiple imputation (MI) is a statistical method, widely adopted in practice, for dealing with missing data. Many academic journals now emphasise the importa...

journal_title：BMC medical research methodology

authors： Hayati Rezvan P,Lee KJ,Simpson JA

更新日期：2015-04-07 00:00:00

abstract：BACKGROUND:Cancer relapses may be useful to predict the risk of death. To take into account relapse information, the Landmark approach is popular. As an alternative, we propose the joint frailty model for a recurrent event and a terminal event to derive dynamic predictions of the risk of death. METHODS:The proposed pr...

journal_title：BMC medical research methodology

authors： Mauguen A,Rachet B,Mathoulin-Pélissier S,Lawrence GM,Siesling S,MacGrogan G,Laurent A,Rondeau V

更新日期：2015-04-01 00:00:00

abstract：BACKGROUND:Patient-reported outcomes (PRO) are important as endpoints in clinical trials and epidemiological studies. Guidelines for the development of PRO instruments and analysis of PRO data have emphasized the need to report methods used for sample size planning. The Raschpower procedure has been proposed for sample...

journal_title：BMC medical research methodology

authors： Blanchin M,Guilleux A,Perrot B,Bonnaud-Antignac A,Hardouin JB,Sébille V

更新日期：2015-03-15 00:00:00

abstract：BACKGROUND:Discrete Choice Experiments (DCEs) are increasingly used in studies in healthcare research but there is still little empirical evidence for the predictive value of these hypothetical situations in similar real life circumstances. The aim of this paper is to compare the stated preferences in a DCE and the acc...

journal_title：BMC medical research methodology

authors： Lambooij MS,Harmsen IA,Veldwijk J,de Melker H,Mollema L,van Weert YW,de Wit GA

更新日期：2015-03-12 00:00:00

abstract：BACKGROUND:Primary-care based randomized controlled trials (RCTs) build an important evidence base for general practice but little evidence exists about barriers to recruitment which often hamper such trials. We investigated the issues that impeded and facilitated recruitment to a clinical trial in general practice. M...

journal_title：BMC medical research methodology

authors： Foster JM,Sawyer SM,Smith L,Reddel HK,Usherwood T

更新日期：2015-03-12 00:00:00

abstract：BACKGROUND:Controlling the false discovery rate is important when testing multiple hypotheses. To enhance the detection capability of a false discovery rate control test, we applied the likelihood ratio-based multiple testing method in neuroimage data and compared the performance with the existing methods. METHODS:We ...

journal_title：BMC medical research methodology

authors： Lee D,Kang H,Kim E,Lee H,Kim H,Kim YK,Lee Y,Lee DS

更新日期：2015-01-30 00:00:00

abstract：BACKGROUND:General Practitioners (GPs) respond poorly to postal surveys. Consequently there is potential for reduced data quality and bias in the findings. In general population surveys, response to postal questionnaires may be improved by reducing their length and offering incentives. The aim of this study was to inve...

journal_title：BMC medical research methodology

authors： Cottrell E,Roddy E,Rathod T,Thomas E,Porcheret M,Foster NE

更新日期：2015-01-06 00:00:00

abstract：BACKGROUND:The aim was to describe a strategy for recruitment of healthy volunteers (HV) to a randomized trial that assessed the efficacy of different telephone techniques to assist HV in performing cardiac massage for vital emergency. Participation in the randomized trial was not financially compensated, however HV we...

journal_title：BMC medical research methodology

authors： Luzurier Q,Damm C,Lion F,Daniel C,Pellerin L,Tavolacci MP

更新日期：2015-01-05 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 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:Syntheses of qualitative studies can inform health policy, services and our understanding of patient experience. Meta-ethnography is a systematic seven-phase interpretive qualitative synthesis approach well-suited to producing new theories and conceptual models. However, there are concerns about the quality ...

journal_title：BMC medical research methodology

authors： France EF,Ring N,Thomas R,Noyes J,Maxwell M,Jepson R

更新日期：2014-11-19 00:00:00

abstract：BACKGROUND:Video stimulated recall (VSR) is a method of enhancing participants' accounts of the consultation using a video recording of the event to encourage and prompt recall in a post consultation interview. VSR is used in education and education research, and to a lesser extent in medical and nursing research. Litt...

journal_title：BMC medical research methodology

authors： Paskins Z,McHugh G,Hassell AB

更新日期：2014-08-30 00:00:00

abstract：BACKGROUND:The Patient Reported Outcomes Measurement Information System 43-item short form (PROMIS-43) and the five-level EQ-5D (EQ-5D-5L) are recently developed measures of health-related quality of life (HRQL) that have potentially broad application in evaluating treatments and capturing burden of respiratory-related...

journal_title：BMC medical research methodology

authors： Lin FJ,Pickard AS,Krishnan JA,Joo MJ,Au DH,Carson SS,Gillespie S,Henderson AG,Lindenauer PK,McBurnie MA,Mularski RA,Naureckas ET,Vollmer WM,Lee TA,CONCERT Consortium.

更新日期：2014-06-16 00:00:00

abstract：BACKGROUND:Chemotherapy is expected to reduce cancer deaths (CD), while possibly being harmful in terms of non-cancer deaths (NCD) because of toxicity. Peto's log-rank test is popular in the medical literature, but its operating characteristics are barely known. We compared this test to the most common ones in the stat...

journal_title：BMC medical research methodology

authors： Rotolo F,Michiels S

更新日期：2014-05-29 00:00:00

abstract：BACKGROUND:Network meta-analysis can be used to combine results from several randomized trials involving more than two treatments. Potential inconsistency among different types of trial (designs) differing in the set of treatments tested is a major challenge, and application of procedures for detecting and locating inc...

journal_title：BMC medical research methodology

authors： Piepho HP

更新日期：2014-05-10 00:00:00

abstract：BACKGROUND:The effectiveness of multiple innovative recruitment strategies for enrolling Black/African American participants to the Adventist Health Study-2 (AHS-2) is described. The study's focus is diet and breast, prostate and colon cancer. METHODS:Promotions centered on trust, relationship building and incentives ...

journal_title：BMC medical research methodology

authors： Herring P,Butler T,Hall S,Bennett H,Montgomery SB,Fraser G

更新日期：2014-04-03 00:00:00

abstract：BACKGROUND:Thresholds for statistical significance are insufficiently demonstrated by 95% confidence intervals or P-values when assessing results from randomised clinical trials. First, a P-value only shows the probability of getting a result assuming that the null hypothesis is true and does not reflect the probabilit...

journal_title：BMC medical research methodology

authors： Jakobsen JC,Gluud C,Winkel P,Lange T,Wetterslev J

更新日期：2014-03-04 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:Diagnostic problems in clinical trials are sometimes ordinal. For example, colon tumor staging was performed according to the TNM classification. However, clinical data are limited by markedly small sample sizes in some stage. METHODS:We propose a distribution-free test for detecting ordered alternatives in...

journal_title：BMC medical research methodology

authors： Chang CH,Chin CC,Yu WW,Huang YY

更新日期：2013-12-05 00:00:00

abstract：BACKGROUND:Recruiting deaf and hard-of-hearing participants, particularly sign language-users, for genetics health service research is challenging due to communication barriers, mistrust toward genetics, and researchers' unfamiliarity with deaf people. Feelings of social exclusion and lack of social cohesion between re...

journal_title：BMC medical research methodology

authors： Kobayashi Y,Boudreault P,Hill K,Sinsheimer JS,Palmer CG

更新日期：2013-11-25 00:00:00

abstract：BACKGROUND:International clinical trials are now rapidly expanding into Asia. However, the proportion of global trials is higher in South Korea compared to Japan despite implementation of similar governmental support in both countries. The difference in clinical trial environment might influence the respective physicia...

journal_title：BMC medical research methodology

authors： Ito-Ihara T,Hong JH,Kim OJ,Sumi E,Kim SY,Tanaka S,Narita K,Hatta T,Choi EK,Choi KJ,Miyagawa T,Minami M,Murayama T,Yokode M

更新日期：2013-10-25 00:00:00

abstract：BACKGROUND:Epidemiologic studies often struggle to adequately represent populations and outcomes of interest. Differences in methodology, data analysis and research questions often mean that reviews and synthesis of the existing literature have significant limitations. The current paper details our experiences in combi...

journal_title：BMC medical research methodology

authors： Allen J,Inder KJ,Lewin TJ,Attia JR,Kay-Lambkin FJ,Baker AL,Hazell T,Kelly BJ

更新日期：2013-10-05 00:00:00

abstract：BACKGROUND:Sickness absence (SA) is an important social, economic and public health issue. Identifying and understanding the determinants, whether biological, regulatory or, health services-related, of variability in SA duration is essential for better management of SA. The conditional frailty model (CFM) is useful whe...

journal_title：BMC medical research methodology

authors： Torá-Rocamora I,Gimeno D,Delclos G,Benavides FG,Manzanera R,Jardí J,Alberti C,Yasui Y,Martínez JM

更新日期：2013-09-16 00:00:00

abstract：BACKGROUND:Primary care databases are a major source of data for epidemiological and health services research. However, most studies are based on coded information, ignoring information stored in free text. Using the early presentation of rheumatoid arthritis (RA) as an exemplar, our objective was to estimate the exten...

journal_title：BMC medical research methodology

authors： Ford E,Nicholson A,Koeling R,Tate A,Carroll J,Axelrod L,Smith HE,Rait G,Davies KA,Petersen I,Williams T,Cassell JA

更新日期：2013-08-21 00:00:00

abstract：BACKGROUND:The rationale for commissioning community pulmonary rehabilitation programmes is based on evidence from randomised clinical trials. However, there are a number of reasons why similar programmes might be less effective outside the environment of a clinical trial. These include a less highly selected patient g...

journal_title：BMC medical research methodology

authors： Goyder EC,Strong M,Green A,Holmes MW,Miles G,Reddington O,Lawson R,Lee A,Basran G

更新日期：2013-08-13 00:00:00

abstract：BACKGROUND:In longitudinal studies where subjects experience recurrent incidents over a period of time, such as respiratory infections, fever or diarrhea, statistical methods are required to take into account the within-subject correlation. METHODS:For repeated events data with censored failure, the independent increm...

journal_title：BMC medical research methodology

authors： Villegas R,Julià O,Ocaña J

更新日期：2013-07-24 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:The Pathobiology of Prediabetes in A Biracial Cohort study is a prospective evaluation of the transition from normal to impaired glucose regulation among African American and Caucasian adults with parental type 2 diabetes. This report describes recruitment strategies and relative yields for the 376 enrolled ...

journal_title：BMC medical research methodology

authors： Ebenibo S,Edeoga C,Ammons A,Egbuonu N,Dagogo-Jack S,Pathobiology of Prediabetes in a Biracial Cohort (POP-ABC) Research Group.

更新日期：2013-05-10 00:00:00

abstract：BACKGROUND:Models of hepatitis C virus (HCV) kinetics are increasingly used to estimate and to compare in vivo drug's antiviral effectiveness of new potent anti-HCV agents. Viral kinetic parameters can be estimated using non-linear mixed effect models (NLMEM). Here we aimed to evaluate the performance of this approach ...

journal_title：BMC medical research methodology

authors： Laouénan C,Guedj J,Mentré F

更新日期：2013-04-25 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:Two most important considerations in evaluation of survival prediction models are 1) predictability - ability to predict survival risks accurately and 2) reproducibility - ability to generalize to predict samples generated from different studies. We present approaches for assessment of reproducibility of sur...

journal_title：BMC medical research methodology

authors： Chen HC,Chen JJ

更新日期：2013-02-20 00:00:00

abstract：BACKGROUND:The occurrence of communicable diseases (CD) depends on exposure to contagious persons. The effects of exposure to CD are delayed in time and contagious persons remain contagious for several days during which their contagiousness varies. Moreover when multiple exposures occur, it is difficult to know which e...

journal_title：BMC medical research methodology

authors： Payet C,Voirin N,Vanhems P,Ecochard R

更新日期：2013-02-20 00:00:00

abstract：BACKGROUND:Diabetes-related lower limb amputations are associated with considerable morbidity and mortality and are usually preceded by foot ulceration. The available systematic reviews of aggregate data are compromised because the primary studies report both adjusted and unadjusted estimates. As adjusted meta-analyses...

journal_title：BMC medical research methodology

authors： Crawford F,Anandan C,Chappell FM,Murray GD,Price JF,Sheikh A,Simpson CR,Maxwell M,Stansby GP,Young MJ,Abbott CA,Boulton AJ,Boyko EJ,Kastenbauer T,Leese GP,Monami M,Monteiro-Soares M,Rith-Najarian SJ,Veves A,Coates N

更新日期：2013-02-15 00:00:00

abstract：BACKGROUND:Competing risks are a common occurrence in survival analysis. They arise when a patient is at risk of more than one mutually exclusive event, such as death from different causes, and the occurrence of one of these may prevent any other event from ever happening. METHODS:There are two main approaches to mode...

journal_title：BMC medical research methodology

authors： Hinchliffe SR,Lambert PC

更新日期：2013-02-06 00:00:00

abstract：BACKGROUND:Although in health services survey research we strive for a high response rate, this must be balanced against the need to recruit participants ethically and considerately, particularly in surveys with a sensitive nature. In survey research there are no established recommendations to guide recruitment approac...

journal_title：BMC medical research methodology

authors： Hunt KJ,Shlomo N,Addington-Hall J

更新日期：2013-01-11 00:00:00

abstract：BACKGROUND:E1684 was the pivotal adjuvant melanoma trial for establishment of high-dose interferon (IFN) as effective therapy of high-risk melanoma patients. E1690 was an intriguing effort to corroborate E1684, and the differences between the outcomes of these trials have embroiled the field in controversy over the pas...

journal_title：BMC medical research methodology

authors： Ibrahim JG,Chen MH,Chu H

更新日期：2012-11-29 00:00:00

abstract：BACKGROUND:Variation in counts between subjects at a given speed or work rate are the most important source of error in physical activity (PA) measurements with accelerometers. The aim of this study was to explore how the use of individual accelerometer cut points (ICPs) affected the analysis of PA field data. METHODS...

journal_title：BMC medical research methodology

authors： Aadland E,Steene-Johannessen J

更新日期：2012-11-15 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:This paper discusses whether baseline demographic, socio-economic, health variables, length of follow-up and method of contacting the participants predict non-response to the invitation for a second assessment of lifestyle factors and body weight in the European multi-center EPIC-PANACEA study. METHODS:Over...

journal_title：BMC medical research methodology

authors： May AM,Adema LE,Romaguera D,Vergnaud AC,Agudo A,Ekelund U,Steffen A,Orfanos P,Slimani N,Rinaldi S,Mouw T,Rohrmann S,Hermann S,Boeing H,Bergmann MM,Jakobsen MU,Overvad K,Wareham NJ,Gonzalez C,Tjonneland A,Halkjaer

更新日期：2012-09-24 00:00:00