Saturday, September 29, 2012
The basic principles of assessment provide a fundamental understanding of statistics. Utilizing means and standard deviations in the analysis of empirical study helps counselors understand the value and effectiveness of an intervention or a technique. Balkin, Tietjen-Smith, Caldwell, and Shen (2007) determined that counselors can make reliable recommendations for exercise and its ameliorative properties for mild and moderate depression based on measurements obtained by utilizing the Beck Depression Inventory-II on participants.
From the descriptive statistics in Table 1 (Balkin, Tietjen-Smith, Caldwell, & Shen, 2007), the aerobic exercise group demonstrated the largest gain with a 29% decrease in depressive symptoms. The anaerobic group showed a 24% decrease, and the control group showed the least gain with a 20% decrease in depressive symptoms. (Percentages are approximate). These decreases were calculated based solely on the mean results of the three groups. Taking into consideration the inconsistency in the response measured by the standard deviations of each group, Balkin, Tietjen-Smith, Caldwell, and Shen (2007) found the aerobic group experienced the most benefit and the anaerobic group experienced less of a benefit than the aerobic group and the control group. Although the positive effects of weight lifting or other anaerobic exercise may exist, a significant effect on depressive symptoms was not apparent in this study (Balkin, Tietjen-Smith, Caldwell, & Shen, 2007).
Most and Least Consistent Responses
In the posttests for all three groups, using the standard deviation as the determinant of consistency, the aerobic group had the smallest standard deviation, meaning the responses of that group were most consistent. The anaerobic group responded least consistently as evidenced by the widest standard deviation. When used in assessments, the standard deviation demonstrates the extent to which the scores vary from the mean score (Whiston, 2008). The smaller the standard deviation, the closer to the mean the scores varied, whereas the larger the standard deviation, the more the scores deviated from the mean score. Larger standard deviations show less consistency in the response and smaller standard deviations show a more consistent response (Whiston, 2008).
Recommending Exercise for Mild to Moderate Depression
Although Bass, Enochs, and DiBrezzo (2002) found results to the contrary, research across a variety of populations determined that aerobic exercise has ameliorative properties for depressive symptoms in mild to moderate depression (Aan het Rot, Collins, & Fitterling, 2009; Johnson et al., 2008; Nabkasorn, 2005; Ströhle, 2009). Barring any medical contraindications, when counseling individuals with mild to moderate depression, I would recommend a program of regular aerobic exercise. Although any type of exercise may have some health benefits, aerobic exercise may have the most meaningful benefit in improving mood and ameliorating depressive symptoms (Balkin, Tietjen-Smith, Caldwell, & Shen, 2007; Eriksson & Gard, 2011).
Strength and Limitation of the Principles of Assessments
Basic assessment principles give counselors the foundational guidelines by which to understand the purpose of assessments and translate their results into practical and useable applications in counseling (Whiston, 2008). If counselors wish to draw conclusions based on an assessment or interpret the meaning of their results in specific circumstances, they must understand the fundamental precepts of assessment. This common language provides a basis for communicating results and using the data appropriately (McMillan, 2000). The principles of assessments help counselors follow the established guidelines so they can make professional judgments based on the assessments they utilize. For example, Balkin, Tietjen-Smith, Caldwell, and Shen (2007) used the means and standard deviations of participant scores to demonstrate the effects of aerobic versus anaerobic exercise on depression. Utilizing the information in this study enables counselors to make empirically derived recommendations to clients with depressive symptoms.
One limitation in this study and in studies in general is obtaining an adequate sample that is representative of a larger population to which the results can be applied. In Balkin, Tietjen-Smith, Caldwell, and Shen (2007), the sample size was small and representative of a particular segment of the larger population. When samples are small, they are less apt to apply to larger populations. The same can be said of samples that do not include members of diverse populations. The selection process for enlisting participants can be challenging because of the improbable nature of including representation from diverse populations (Whiston, 2008). Random sampling is difficult for a study like Balkin, Tietjen-Smith, Caldwell, and Shen's (2007), so the results are only applicable to the represented young adult population.
Understanding basic assessment principles helps counselors understand and apply the results of assessments. Furthermore, it helps them choose evaluative instruments that will yield the greatest benefit for their clients (Whiston, 2008). The ability to judge assessments as reliable, valid, fair, and ethical supports the effectiveness of counselors as well as the reputation and reliability of the profession.
Aan het Rot, M., Collins, K. A., & Fitterling, H. L. (2009). Physical exercise and depression. Mount Sinai Journal of Medicine: A Journal of Translational and Personalized Medicine, 76(2), 204-214. doi: 10.1002/msj.20094
Balkin, R. S., Tietjen-Smith, T., Caldwell, C., & Shen, Y. (2007). The utilization of exercise to decrease depressive symptoms in young adult women. Adultspan: Theory, Research, & Practice, 6(1), 30-35. doi: 10.1002/j.2161-0029.2007.tb00027.x
Bass, M. A., Enochs, W. K., & DiBrezzo, R. (2002). Comparison Of Two Exercise Programs On General Well-Being Of College Students [Abstract]. Psychological Reports, 91(8), 1195. doi: 10.2466/PR0.91.8.1195-1201
Eriksson, S., & Gard, G. (2011). Physical exercise and depression. Physical Therapy Reviews, 16(4), 261-268. doi: 10.1179/1743288X11Y.0000000026
Johnson, C. C., Murray, D. M., Elder, J. P., Jobe, J. B., Dunn, A. L., Kubik, M., ... Schachter, K. (2008). Depressive Symptoms and Physical Activity in Adolescent Girls. Medicine & Science in Sports & Exercise, 40(5), 818-826. doi: 10.1249/MSS.0b013e3181632d49
McMillan, J. H. (2000). Fundamental assessment principles for teachers and school administrators. Practical Assessment, Research & Evaluation, 7(8). Retrieved September 20, 2012, from http://pareonline.net/getvn.asp?v=7&n=8
Nabkasorn, C. (2005). Effects of physical exercise on depression, neuroendocrine stress hormones and physiological fitness in adolescent females with depressive symptoms. The European Journal of Public Health, 16(2), 179-184. doi: 10.1093/eurpub/cki159
Ströhle, A. (2009). Physical activity, exercise, depression and anxiety disorders. Journal of Neural Transmission, 116(6), 777-784. doi: 10.1007/s00702-008-0092-x