Experiment and Observation

Observational study

1. http://www.theatlantic.com/health/archive/2014/04/study-exercise-helps-aging-brains-grow-larger/360291/ – ‘Exercise Helps Aging Brains Grow Larger’
2. The study utilized the stratified random sample technique to collect samples. This is evident since the researchers decided to select aged individuals to be the study samples. They narrowed down to studying aged women, categorized in various ages groups and finally opted to study women aged seventy to eighty years old.
3. The study involved eighty-six participants (aged women) sourced from two countries namely: Canada and the Netherlands (Theatlantic, 2014)
4. The sample size was largely inadequate since in involved only eighty-six women in two countries. This sample inadequately represents the actual number of aged women in the two nations. The sample should be bigger like two hundred to give a better representation along with providing viable study results. This sample should also have involved men in order to acquire the full study results regarding the influence of exercise on all aged individuals (both women and men)
5. The trainings took place for twenty-six weeks. The variables being measured were each of the participant’s hippocampus volume along with a verbal learning evaluation performance, which involved repeating phrases spoken loudly to them. The hippocampus is the brain region connected with memory and its atrophy is linked with Alzheimer’s disease (Theatlantic, 2014). Verbal learning evaluation was categorical and hippocampus volume measurement was qualitative
6. The results were not displayed on a graph and the most appropriate graph that should have been used is the line graph since it would clearly show the results of the study along with easy to interpret. The line graph would show the margins within which the hippocampus volume of each woman increased after the twenty-six week exercise. This would be achieved by grouping women who have attained equal hippocampus volume increase. Then plotting the hippocampus volume increase against the frequency of the number of women who attained the particular increase.   
7. The potential source of bias is under-coverage. The participants were eighty six in two nations that mean that the study might have picked forty-three women in every nation. This represents a small number of women in both countries. Additionally, researchers found that the increase in hippocampus volume did not result to good performances in verbal studying evaluation as expected, this shows that the conclusion was somewhat biased. Another potential source of bias regards the fact that some participants might have had hearing disabilities, thus making verbal learning evaluation biased. The research does not indicate that this aspect was taken into account.
8. This study could be improved through adding the number participants and also the number of countries in order to provide a well encompassing study. The number of participants was too small compared to the women populations in Canada and Netherlands. Additionally, the study should also included a parallel study involving aged men within the same age groups to ensure a balanced research and reliable findings. This study additionally should have involved consumption of certain diets as part of the study. This is because exercise should go hand in hand with particular types of foods to make it more efficient.
9. This study can be turned into an experiment through administering certain medicinal drugs to the aged women in place for exercises. This would be in appropriate since it is unnatural and could have side effects.

References

Theatlantic. (2014). Study: Exercise Helps Aging Brains Grow Larger – The Atlantic. Retrieved from http://www.theatlantic.com/health/archive/2014/04/study-exercise-helps-aging-brains-grow-larger/360291/