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Chest Jul 2020Sample size determination is an essential step in planning a clinical study. It is critical to understand that different study designs need different methods of sample... (Review)
Review
Sample size determination is an essential step in planning a clinical study. It is critical to understand that different study designs need different methods of sample size estimation. Although there is a vast literature discussing sample size estimation, incorrect or improper formulas continue to be applied. This article reviews basic statistical concepts in sample size estimation, discusses statistical considerations in the choice of a sample size for randomized controlled trials and observational studies, and provides strategies for reducing sample size when planning a study. To assist clinical researchers in performing sample size calculations, we have developed an online calculator for common clinical study designs. The calculator is available at http://riskcalc.org:3838/samplesize/. Finally, we offer our recommendations on reporting sample size determination in clinical studies.
Topics: Humans; Observational Studies as Topic; Randomized Controlled Trials as Topic; Research Design; Sample Size
PubMed: 32658647
DOI: 10.1016/j.chest.2020.03.010 -
BMJ Quality & Safety Jul 2020Double checking medication administration in hospitals is often standard practice, particularly for high-risk drugs, yet its effectiveness in reducing medication... (Review)
Review
BACKGROUND
Double checking medication administration in hospitals is often standard practice, particularly for high-risk drugs, yet its effectiveness in reducing medication administration errors (MAEs) and improving patient outcomes remains unclear. We conducted a systematic review of studies evaluating evidence of the effectiveness of double checking to reduce MAEs.
METHODS
Five databases (PubMed, Embase, CINAHL, Ovid@Journals, OpenGrey) were searched for studies evaluating the use and effectiveness of double checking on reducing medication administration errors in a hospital setting. Included studies were required to report any of three outcome measures: an effect estimate such as a risk ratio or risk difference representing the association between double checking and MAEs, or between double checking and patient harm; or a rate representing adherence to the hospital's double checking policy.
RESULTS
Thirteen studies were identified, including 10 studies using an observational study design, two randomised controlled trials and one randomised trial in a simulated setting. Studies included both paediatric and adult inpatient populations and varied considerably in quality. Among three good quality studies, only one showed a significant association between double checking and a reduction in MAEs, another showed no association, and the third study reported only adherence rates. No studies investigated changes in medication-related harm associated with double checking. Reported double checking adherence rates ranged from 52% to 97% of administrations. Only three studies reported if and how independent and primed double checking were differentiated.
CONCLUSION
There is insufficient evidence that double versus single checking of medication administration is associated with lower rates of MAEs or reduced harm. Most comparative studies fail to define or investigate the level of adherence to independent double checking, further limiting conclusions regarding effectiveness in error prevention. Higher-quality studies are needed to determine if, and in what context (eg, drug type, setting), double checking produces sufficient benefits in patient safety to warrant the considerable resources required. CRD42018103436.
Topics: Databases, Factual; Humans; Medication Errors; Observational Studies as Topic; Pharmaceutical Preparations; Randomized Controlled Trials as Topic
PubMed: 31391315
DOI: 10.1136/bmjqs-2019-009552 -
Journal of the International Society of... 2022Tendinopathy is a painful condition that is prevalent in athletes as well as the general human population, and whose management is challenging. (Review)
Review
BACKGROUND
Tendinopathy is a painful condition that is prevalent in athletes as well as the general human population, and whose management is challenging.
OBJECTIVE
This systematic review aimed to evaluate the impact of nutrition on the prevention and treatment of tendinopathy.
METHODS
Searches were conducted in PubMed, EMBASE, Web of Science, and SPORTDiscus without restriction to year of publication. Studies examining the impact of exposure to nutrient intake in an adult human population on 1) prevalence/incidence of tendinopathy, 2) clinical outcomes of tendinopathy, 3) structural changes in the tendon by imaging modalities. Experimental and observational study designs written in English, Dutch, or German were eligible.
RESULTS
Nineteen studies met the inclusion criteria. The effects of the habitual diet were investigated in one study. Four studies examined the effects of exposure to alcohol. Alcohol consumption can be a potential risk factor associated with Achilles tendinopathy and rotator cuff tears, although findings were inconsistent. The use of dietary supplements was examined in fourteen studies. Among these, collagen-derived peptides were most often part of the supplements evaluated. Combining training and dietary supplements seems to induce better clinical and functional outcomes in tendinopathy.
CONCLUSION
This review demonstrates the paucity of high-quality studies and a wide variety among studies regarding nutrients, tendon location, study population, and reported outcome measures. Individual studies showed promising clinical implications for the use of dietary supplements, particularly those containing collagen-derived peptides. However, giving any definitive dietary recommendations on the prevention and treatment of tendinopathy remains elusive.
Topics: Achilles Tendon; Adult; Diet; Dietary Supplements; Humans; Nutritional Status; Observational Studies as Topic; Tendinopathy
PubMed: 35937777
DOI: 10.1080/15502783.2022.2104130 -
JAMA Dec 2022
Topics: Causality; Comparative Effectiveness Research; Research Design; Observational Studies as Topic
PubMed: 36508210
DOI: 10.1001/jama.2022.21383 -
Nature Medicine Nov 2021The particularly interdisciplinary nature of human microbiome research makes the organization and reporting of results spanning epidemiology, biology, bioinformatics,... (Review)
Review
The particularly interdisciplinary nature of human microbiome research makes the organization and reporting of results spanning epidemiology, biology, bioinformatics, translational medicine and statistics a challenge. Commonly used reporting guidelines for observational or genetic epidemiology studies lack key features specific to microbiome studies. Therefore, a multidisciplinary group of microbiome epidemiology researchers adapted guidelines for observational and genetic studies to culture-independent human microbiome studies, and also developed new reporting elements for laboratory, bioinformatics and statistical analyses tailored to microbiome studies. The resulting tool, called 'Strengthening The Organization and Reporting of Microbiome Studies' (STORMS), is composed of a 17-item checklist organized into six sections that correspond to the typical sections of a scientific publication, presented as an editable table for inclusion in supplementary materials. The STORMS checklist provides guidance for concise and complete reporting of microbiome studies that will facilitate manuscript preparation, peer review, and reader comprehension of publications and comparative analysis of published results.
Topics: Computational Biology; Dysbiosis; Humans; Microbiota; Observational Studies as Topic; Research Design; Translational Science, Biomedical
PubMed: 34789871
DOI: 10.1038/s41591-021-01552-x -
Journal of Traditional Chinese Medicine... Aug 2020To analyze clinical studies on correlations between Traditional Chinese Medicine (TCM) body constitution types and diseases published in the past 10 years, and to... (Review)
Review
OBJECTIVE
To analyze clinical studies on correlations between Traditional Chinese Medicine (TCM) body constitution types and diseases published in the past 10 years, and to provide an evidence base to support the use of such correlations for health maintenance and disease prevention.
METHODS
We searched five databases for the period April 2009 to December 2019: China National Knowledge Infrastructure Database, Wanfang Database, China Science and Technology Journal Database, PubMed and Embase. Three types of observational studies on correlation between constitution types and diseases were included: cross-sectional, case-control and cohort studies. Descriptive statistical methods were employed for data analysis.
RESULTS
A total of 1639 clinical studies were identified: 1452 (88.59%) cross-sectional studies, 115 (7.02%) case-control studies and 72 (4.39%) cohort studies covering 30 regions of China and five other countries (Malaysia, South Korea, Singapore, Thailand and France). The collection of studies comprised 19 disease categories and 333 different diseases. The 10 most commonly studied diseases were hypertension, diabetes, stroke, coronary atherosclerotic heart disease (CAHD), sleep disorders, neoplasm of the breast, dysmenorrhea, fatty liver disease, chronic viral hepatitis B and dyslipidemia. We found high distributions for each biased constitution type in different patient populations as follows: Qi-deficiency constitution in stroke, diabetes, chronic obstructive pulmonary disease, acquired immunodeficiency syndrome and hypertension; Yang-deficiency constitution in female infertility, osteoporosis, irritable bowel syndrome, gonarthrosis and dysmenorrhea; Yin-deficiency constitution in hypertension, diabetes, constipation, female climacteric states and osteoporosis; phlegm- dampness constitution in hypertension, stroke, fatty liver disease, diabetes and metabolic syndrome; damp-heat constitution in acne, chronic gastritis, chronic viral hepatitis B, human papillomavirus infection and hyperuricemia; blood-stasis constitution in CAHD, endometriosis and stroke; Qi-stagnation constitution in hyperplasia and neoplasms of the breast, insomnia, depression and thyroid nodules; and inherited-special constitution in asthma and allergic rhinitis.
CONCLUSION
Eight biased TCM constitutions were closely related to specific diseases, and could be used to guide individualized prevention and treatment. More rigorously designed studies are recommended to further verify the constitution-disease relationship.
Topics: Drug Therapy; Drugs, Chinese Herbal; Humans; Medicine, Chinese Traditional; Observational Studies as Topic; Treatment Outcome
PubMed: 32744037
DOI: 10.19852/j.cnki.jtcm.2020.04.019 -
Respiratory Care Nov 2023Studies can be observational or experimental. With an observational study, the investigator does not determine the assignment of subjects, and there might not be a...
Studies can be observational or experimental. With an observational study, the investigator does not determine the assignment of subjects, and there might not be a control group. If there is a control group, assignment of the independent variable (exposure or intervention) is not under the control of the investigator. Observational studies can be rigorously conducted, but the lack of random assignment of the exposure/intervention introduces confounding and bias. Thus, the quality of evidence resulting from observational studies is lower than that of experimental randomized controlled trials (RCTs). An observational study might be performed if an RCT is unethical, impractical, or outside the control of the investigator. There are many types of prospective and retrospective observational study designs. However, an observational study design should be avoided if an experimental study is possible. Sophisticated statistical approaches can be used, but this does not elevate an observational study to the level of an RCT. Regardless of quality, an observational study cannot establish causality.
Topics: Research Design; Observational Studies as Topic
PubMed: 37339891
DOI: 10.4187/respcare.11170 -
BMJ (Clinical Research Ed.) Oct 2021Mendelian randomisation (MR) studies allow a better understanding of the causal effects of modifiable exposures on health outcomes, but the published evidence is often...
Mendelian randomisation (MR) studies allow a better understanding of the causal effects of modifiable exposures on health outcomes, but the published evidence is often hampered by inadequate reporting. Reporting guidelines help authors effectively communicate all critical information about what was done and what was found. STROBE-MR (strengthening the reporting of observational studies in epidemiology using mendelian randomisation) assists authors in reporting their MR research clearly and transparently. Adopting STROBE-MR should help readers, reviewers, and journal editors evaluate the quality of published MR studies. This article explains the 20 items of the STROBE-MR checklist, along with their meaning and rationale, using terms defined in a glossary. Examples of transparent reporting are used for each item to illustrate best practices.
Topics: Epidemiologic Research Design; Guidelines as Topic; Humans; Mendelian Randomization Analysis; Observational Studies as Topic
PubMed: 34702754
DOI: 10.1136/bmj.n2233 -
Atencion Primaria May 2022To evaluate the experiencie with a health education program in Primary Care in patients with chronic shoulder pain of musculoskeletal origin, on pain and disability and... (Observational Study)
Observational Study
OBJECTIVE
To evaluate the experiencie with a health education program in Primary Care in patients with chronic shoulder pain of musculoskeletal origin, on pain and disability and establish the protocol in primary care.
DESIGN
Quasi-experimental longitudinal descriptive observational study.
LOCATION
Arroyo de la Vega Health Center, Alcobendas, Madrid.
PARTICIPANTS
Patients referred by their Primary Care Physician to the Primary Care Physiotherapy Unit for shoulder pain of musculoskeletal origin.
INTERVENTION
7 group sessions of health education and therapeutic exercise.
MAIN MEASUREMENTS
Pain intensity was assessed through the Visual Analogue Scale (VAS), the disability of the upper limb with the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and the level of disability and shoulder pain with the Shoulder Pain and Disability Index (SPADI) questionnaire.
RESULTS
Statistically significant differences were found in the reduction of pain and disability (P<.01), in addition, drug use and recurrences were reduced.
CONCLUSIONS
The shoulder physiotherapy protocol with health education was effective in reducing pain and disability in patients with chronic shoulder pain of musculoskeletal origin in Primary Care.
Topics: Chronic Pain; Health Education; Humans; Musculoskeletal Pain; Observational Studies as Topic; Physical Therapy Modalities; Primary Health Care; Shoulder; Shoulder Pain; Upper Extremity
PubMed: 35461039
DOI: 10.1016/j.aprim.2022.102284 -
Headache Jul 2019
Topics: Epidemiologic Studies; Humans; Migraine Disorders; Observational Studies as Topic; Research Design
PubMed: 31297809
DOI: 10.1111/head.13572