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Involving older adults in design research
Published in Sara J. Czaja, Walter R. Boot, Neil Charness, Wendy A. Rogers, Designing for Older Adults, 2019
Sara J. Czaja, Walter R. Boot, Neil Charness, Wendy A. Rogers
The size of the sample is another important sampling issue: how many people should be included in a research activity to produce meaningful results? The necessary sample size will vary according to the study design and the goals of the activity. For example, the number of participants needed for a proof of concept, usability trial, or focus group study will differ from that of a larger efficacy trial. Efficacy trials usually involve a comparison between two or more groups. For example, in our trial evaluating the efficacy of a computer-based system (Personal Reminder Information and Social Management, PRISM) with respect to reducing isolation and loneliness among older adults, we compared two groups – the PRISM group that received the computer system and a control group that received content similar to PRISM in a paper binder.
Cervical Dysplasia Diagnosis with Fluorescence Spectroscopy
Published in Mary-Ann Mycek, Brian W. Pogue, Handbook of Biomedical Fluorescence, 2003
Rebecca Richards-Kortum, Rebekah Drezek, Karen Basen-Engquist, Scott B. Cantor, Urs Utzinger, Carrie Brookner, Michele Follen
Sample size calculations are affected by several aspects of study design: the number of treatment groups to be studied, the outcome measure of interest, the detectable treatment difference, the desired level of significance, the desired power, the allocation ratio, and the degree of stratification for baseline factors [52]. Most sample size formulas include in the numerator the level of significance and power, and in the denominator the anticipated treatment difference. Considerations for determining a sample size for cervical studies include the anticipated sensitivity and specificity of the device to be tested and the standard of care, the level of significance, the power, and stratification by epidemiological factors of interest such as age, hormonal status, and degree of disease.
Instrument evaluation
Published in C M Langton, C F Njeh, The Physical Measurement of Bone, 2016
Christopher F Njeh, Didier Hans
A successful clinical evaluation starts with a solid understanding of its goals and the establishment of appropriate hypotheses to be tested. Then, an appropriate study design is chosen to produce results that will test these study hypotheses and calculate the right sample size for a given power. The two main categories of study design are longitudinal studies which investigate changes over time or cross-sectional studies which mostly focus on describing a state or phenomenon at a fixed or an indefinite time. The latter are usually relatively inexpensive and are easier to conduct for rare events and are the most frequently used in osteoporosis research. For detailed discussion refer to Lu and Gluer [7, 20]
Sustainable roadway construction: Economic and social impacts of roadways in the context of Ethiopia
Published in Cogent Engineering, 2021
A study design or frame is the process that guides the researcher on how to collect, analyzes, and interprets observations. Having this in mind this section shows the procedures and methodology that the researcher follows to compare the economic impact of JCP and HMA pavement by investigating their life cycle costs. Hence, to achieve the aim, the following tasks had been performed: