Publication of statistically significant research findings in prosthodontics & implant dentistry in the context of other dental specialties

OBJECTIVES To assess the hypothesis that there is excessive reporting of statistically significant studies published in prosthodontic and implantology journals, which could indicate selective publication. METHODS The last 30 issues of 9 journals in prosthodontics and implant dentistry were hand-searched for articles with statistical analyses. The percentages of significant and non-significant results were tabulated by parameter of interest. Univariable/multivariable logistic regression analyses were applied to identify possible predictors of reporting statistically significance findings. The results of this study were compared with similar studies in dentistry with random-effects meta-analyses. RESULTS From the 2323 included studies 71% of them reported statistically significant results, with the significant results ranging from 47% to 86%. Multivariable modeling identified that geographical area and involvement of statistician were predictors of statistically significant results. Compared to interventional studies, the odds that in vitro and observational studies would report statistically significant results was increased by 1.20 times (OR: 2.20, 95% CI: 1.66-2.92) and 0.35 times (OR: 1.35, 95% CI: 1.05-1.73), respectively. The probability of statistically significant results from randomized controlled trials was significantly lower compared to various study designs (difference: 30%, 95% CI: 11-49%). Likewise the probability of statistically significant results in prosthodontics and implant dentistry was lower compared to other dental specialties, but this result did not reach statistical significant (P>0.05). CONCLUSIONS The majority of studies identified in the fields of prosthodontics and implant dentistry presented statistically significant results. The same trend existed in publications of other specialties in dentistry.

Reporting quality of randomised controlled trials published in prosthodontic and implantology journals

The purpose of this study was to examine the reporting quality of randomised controlled trials (RCTs) published in prosthodontic and implantology journals. Thirty issues of nine journals in prosthodontics and implant dentistry were searched for RCTs, covering the years 2005-2012: The Journal of Prosthetic Dentistry, Journal of Oral Rehabilitation, The International Journal of Prosthodontics, The International Journal of Periodontics & Restorative Dentistry, Clinical Oral Implants Research, Clinical Implant Dentistry & Related Research, The International Journal of Oral & Maxillofacial Implants, Implant Dentistry and Journal of Dentistry. The reporting quality was assessed using a modified Consolidated Standards of Reporting Trials (CONSORT) statement checklist. Data were analysed using descriptive statistics followed by univariable and multivariable examination of statistical associations (α = 0·05). A total of 147 RCTs were identified with a mean CONSORT score of 69·4 (s.d. = 9·7). Significant differences were found among journals with the Journal of Oral Rehabilitation achieving the highest score (80·6, s.d. = 5·5) followed by Clinical Oral Implants Research (73·7, s.d. = 8·3). Involvement of a statistician/methodologist was significantly associated with increased CONSORT scores. Overall, the reporting quality of RCTs in major prosthodontic and implantology journals requires improvement. This is of paramount importance considering that optimal reporting of RCTs is an important prerequisite for clinical decision-making.

Continuous safety screens for randomized controlled clinical trials with blinded treatment information

Standard methods for testing safety data are needed to ensure the safe conduct of clinical trials. In particular, objective rules for reliably identifying unsafe treatments need to be put into place to help protect patients from unnecessary harm. DMCs are uniquely qualified to evaluate accumulating unblinded data and make recommendations about the continuing safe conduct of a trial. However, it is the trial leadership who must make the tough ethical decision about stopping a trial, and they could benefit from objective statistical rules that help them judge the strength of evidence contained in the blinded data. We design early stopping rules for harm that act as continuous safety screens for randomized controlled clinical trials with blinded treatment information, which could be used by anyone, including trial investigators (and trial leadership). A Bayesian framework, with emphasis on the likelihood function, is used to allow for continuous monitoring without adjusting for multiple comparisons. Close collaboration between the statistician and the clinical investigators will be needed in order to design safety screens with good operating characteristics. Though the math underlying this procedure may be computationally intensive, implementation of the statistical rules will be easy and the continuous screening provided will give suitably early warning when real problems were to emerge. Trial investigators and trial leadership need these safety screens to help them to effectively monitor the ongoing safe conduct of clinical trials with blinded data.^

Intraoperative changes in platelet function in relation to moderate haemorrhage

Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved. Funding The study was funded by TENOVUS Scotland (G12/14). Jan Jansen is in receipt of salary support through the NHS Research Scotland (NRS) fellowship scheme. Acknowledgements The authors are extremely grateful for the expert assistance and contributions of Dr Neil Scott (Medical Statistician, University of Aberdeen), Win Culley (Research Nurse, Woodend Hospital), Dr Karen Cranfield (Consultant Anaesthetist), and Ms Sharon Wood, (Research Technician, Rowett Institute of Nutrition and Health) for fibrinogen measurement.

Women's Volleyball Team, 1993, UM

Front Row: Karen Jacobsen, Marita McCahill, Michelle Horrigan, Fiona Davidson, JoAnna Collias, Erica Badran-Grycan.

Second Row: athletic trainer Keli Coughlin, Robin Read, Aimee Smith, Suzy O'Donnell, Julie Scherer.

Third Row: Jessica Ping, Shareen Luze, Darlene Recker, Shannon Brownlee, Erin McGovern.

Back Row: manager Dave Fleming, assistant coach Mora Kanim, head coach Greg Giovanazzi, assistant coach Jennifer Dhaenens, statistician Duane Storti

Not Pictured: Ramona Cox, Meg Akehi

Blue book for the year ... /

Chiefly tables.

Procedures used in compiling monthly statistics relating to employment and pay rolls.

Reproduced from type-written copy.

Mortality rates 1910-1920 with population of the federal censuses of 1910 and 1920 and intercensal estimates of population.

"Prepared under the direction of Dr. William H. Davis, chief statistician for vital statistics, and under the immediate supervision of Richard C. Lappin, expert special agent of the Bureau of the Census.--Letter of transmittal, p. 5.

Bulletin /

Contents: No.2(1897) - Synoptical index of the reports of the Statistician, 1863 to 1894; no.4(1898) - Index to authors with titles of their publications appearing in documents of the U.S. Department of Agriculture, 1841 to 1897; no.6(1902) - List by titles of publications of the United States Department of Agriculture from 1840 to June, 1901, inclusive ...; no.7(1902) - Index to the Yearbooks of the U.S. Department of Agriculture, 1894-1900; no.8(1907) - Index to Farmers' bulletins Nos.1-250.

Manual of the international list of causes of death : based on the 3rd decennial revision of the International Commission, Paris, Octobe 11 to 15, 1920.

At head of title: Department of Commerce and Labor. Bureau of the Census. W.M. Steuart, director.

Annual report on the statistics of railways in the United States.

1921-1942 contain abstracts of periodical reports.

Statistics of the State of Queensland.

Vols. for 18 -1900, compiled from official records in the Registrar-General's Office; 1901- , compiled from official records in the Government Statistician's Office.

Directory /

"John E. Ford, pastor; J.A. Houston, statistician and compiler."

Official year book of the Commonwealth of Australia.

Issues for 1901/07-1901/20 include corrected statistics for the period 1788 to 1900.

Western Australian year book.

Mode of access: Internet.