Practice Exercises
Week 5
Practice questions
Visit the the link below take the quiz to test your knowledge on this topic.
https://drfurtado.shinyapps.io/Practice-Questions/
The studies below are fictitious.
Practice Exercises - Measures of Central Tendency
Below are several practice exercises for Week 5. Write down your answers, then click Tip at the end of each exercise to review the answers.
For exercises 1-3, fill the blank with wither Mean, Median, or Mode.
Practice exercise 1
A study titled “Symptoms and Quality of Life in Patients with Fibromyalgia: A Cross-Sectional Study” used the ___________ to report the most frequently experienced symptoms by patients with fibromyalgia. The study surveyed 200 patients with fibromyalgia and asked them to report their symptoms using a questionnaire. The questionnaire included questions about 19 different symptoms commonly associated with fibromyalgia, such as pain, fatigue, sleep disturbances, depression, and anxiety.
When reporting the results, the authors used the _________ to describe the most common symptoms experienced by the patients. For example, they reported that the __________ for pain intensity was 7 (on a scale of 0 to 10), indicating that a pain intensity score of 7 was the most frequently reported by patients. The authors also reported the ___________ for each of the other 18 symptoms, such as the ___________ for fatigue severity, sleep quality, and anxiety level.
Using the ___________ in this study allowed the researchers to identify the symptoms that were most commonly reported by patients with fibromyalgia, which could help clinicians to better understand and manage the condition. The ___________ is an appropriate measure of central tendency in this study because it is useful for identifying the most frequently occurring value in a dataset, which can be important information for clinical decision-making.
mode
Practice exercise 2
In this study, the authors aimed to investigate the associations between physical activity, adiposity, cardiorespiratory fitness, and academic performance in a sample of Spanish youth. The authors used a cross-sectional design and recruited 1,700 children aged 6 to 18 years. The authors measured the children’s physical activity using self-report questionnaires, and they measured their adiposity using body mass index (BMI), waist circumference, and skinfold thickness. The authors also assessed the children’s cardiorespiratory fitness using a 20-m shuttle run test, and they measured academic performance using grade point averages.
When reporting the results, the authors used the ___________ instead of the ___________ to describe the distribution of the physical activity and adiposity measures. For example, they reported the ___________ minutes per day spent in moderate-to-vigorous physical activity (MVPA) instead of the ___________ MVPA. The authors chose to use the ___________ because the distributions of the physical activity and adiposity measures were skewed, meaning that a few extreme values could heavily influence the ___________.
Overall, the study found that higher levels of physical activity, lower levels of adiposity, and higher levels of cardiorespiratory fitness were all positively associated with better academic performance in youth. The authors also found evidence to suggest that cardiorespiratory fitness mediated the relationship between physical activity and academic performance.
median, mean, median, mean, median, mean
Practice Exercise 3
In this study, the authors aimed to investigate the effect of caffeine ingestion on tennis skill performance. The authors used a randomized, double-blind, crossover design and recruited 16 male tennis players. The players consumed either caffeine or a placebo before performing a tennis skill test, which consisted of serving, forehand, backhand, and volley. The authors measured the time to complete the skill test, the accuracy of the shots, and the total score of the test.
When reporting the results, the authors used the ___________ instead of the ___________ to describe the central tendency of the data. For example, they reported the ___________ time to complete the skill test instead of the ___________ time. The authors chose to use the ___________ because the distributions of the skill test measures were approximately normal, meaning that the ___________ was a representative value of the data.
Overall, the study found that caffeine ingestion improved tennis skill performance compared to the placebo condition. The authors found significant improvements in the time to complete the skill test, the accuracy of the shots, and the total score of the test. The authors concluded that caffeine ingestion may enhance tennis skill performance and could be used as an ergogenic aid in tennis.
mean, median, mean, median, mean, mean
Practice Exercises - Measures of Variability
For exercises 4-6, fill the blank with either the Interquartile Range, Variance, Range, or Standard Deviation.
Practice Exercise 4
n this study, the authors aimed to investigate the effect of protein supplementation combined with resistance training on muscle mass, strength, and function in individuals with chronic obstructive pulmonary disease (COPD). The authors conducted a systematic review and meta-analysis of randomized controlled trials that evaluated the effect of protein supplementation and resistance training on COPD patients. The authors extracted data on muscle mass, strength, and function outcomes and calculated effect sizes using Hedges’ g.
When reporting the results, the authors used the ___________ instead of the ____________ to describe the dispersion of the effect sizes. The authors chose to use the __________ because the effect size distributions were not normally distributed and contained outliers, which could heavily influence the _________ . The _________ is a more robust measure of dispersion that is less affected by outliers.
Overall, the meta-analysis found that protein supplementation combined with resistance training was effective in improving muscle mass, strength, and function in individuals with COPD. The authors found significant improvements in the outcomes of muscle mass, strength, and function in the protein supplementation group compared to the control group. The authors concluded that protein supplementation combined with resistance training could be a promising intervention for improving muscle health in individuals with COPD.
IQR, Standard Deviation, IQR, Standard Deviation, IQR
Recall that the SD should be reported instead of the variance since the former is aligned to the scale of the original data.
Practice Exercise 5
In this study, the authors aimed to investigate the relationship between physical activity and depressive symptoms in older women. The authors used a cross-sectional design and recruited 198 women aged 65 years and older. The authors measured the women’s physical activity using self-report questionnaires, and they assessed their depressive symptoms using the Geriatric Depression Scale.
When reporting the results, the authors used the ___________ instead of the ____________ to describe the variability of the data. For example, they reported the ___________ of the physical activity levels instead of the ____________ of the physical activity levels. The authors chose to use the ___________ because the distributions of the physical activity levels and the depressive symptoms scores were skewed and had outliers, which could heavily influence the ____________.
Overall, the study found a significant negative relationship between physical activity levels and depressive symptoms scores in older women. The authors also found that the relationship was strongest for moderate-intensity physical activity. The authors concluded that physical activity could be an effective non-pharmacological intervention for preventing and treating depressive symptoms in older women.
IQR, Standard Deviation, IQR, Standard Deviation, IQR, Standard Deviation
Practice Exercise 6
In this study, the authors aimed to investigate the effect of resistance training frequency on neuromuscular performance and muscle morphology in trained men. The authors used a randomized controlled trial design and recruited 28 trained men. The men were randomly assigned to either a high-frequency resistance training group (six sessions per week) or a low-frequency resistance training group (three sessions per week). The authors measured the men’s neuromuscular performance using maximal isometric and dynamic strength tests, and they assessed the muscle morphology using muscle biopsies.
When reporting the results, the authors used the ____________ instead of the ___________ to describe the variability of the data. For example, they reported the ____________ of the maximal isometric strength instead of the ___________ of the maximal isometric strength. The authors chose to use the ____________ because the distributions of the neuromuscular performance measures and the muscle morphology measures were approximately normal, meaning that the ____________ was a representative value of the data.
Overall, the study found that the high-frequency resistance training group had greater improvements in neuromuscular performance and muscle morphology compared to the low-frequency resistance training group. The authors found significant increases in maximal isometric and dynamic strength, muscle cross-sectional area, and myofibrillar protein content in the high-frequency group. The authors concluded that high-frequency resistance training could be a superior training strategy for enhancing neuromuscular performance and muscle morphology in trained men.
Standard Deviation, IQR or Range, Standard Deviation, IQR, Standard Deviation, Standard Deviation