Article Analysis: Population and Sample Size
Article Analysis: Population and Sample Size
Qi, B. B., Resnick, B., Smeltzer, S. C., & Bausell, B. (2011). Self-efficacy program to prevent
osteoporosis among Chinese immigrants: A randomized controlled trial. Nursing research, 60(6), 393-404.
Questions
- Was the population identified and described? Was the sample described in sufficient detail?
The researchers have identified and described the target population adequately. The population targeted in this study is foreign-born, Mandarin speaking Asian adults who were over 45 years old. Describing the target population is important as it allows the people reading the study to appreciate the inclusion criteria and to determine the extendibility of the study. This target population makes this research relevant to nursing practice because the reviewed literature show that recent Chinese migrants have low bone mineral density and are at a risk of osteoporosis (Qi et al., 2011).
- Was the best possible sampling design used to enhance the sample’s representativeness? Were sample biases minimized?
The researchers invited eligible participants though adverts displayed in public places and in Chinese newspapers. This free participation together with randomization done in assigning the participants either to the SEOPE intervention group or to the control group served to minimize sample biases. The free and voluntary participation and public advertisements to invite prospective participants enhanced sample representativeness in that all eligible participants had a chance to participate in the study.
- Was the sample size adequate? Was a power analysis used to estimate sample size needs?
The eligible participants were 111, 83 were randomized to either the control group (n=41) or the intervention group (n=42) and 72 participants persisted to the end of the study and were analyzed. While the researchers had not used a power analysis to determine an estimate sample size needed to meet the study objectives, the researchers cited the small sample size as one of the study limitations. Therefore, a bigger sample size is recommended in future research.
References
Qi, B. B., Resnick, B., Smeltzer, S. C., & Bausell, B. (2011). Self-efficacy program to prevent
osteoporosis among Chinese immigrants: A randomized controlled trial. Nursing research, 60(6), 393-404.
