Do study the book "Communication for Development and Social change". Page 112. I am sure that your problem will be solved.

Mathur, K. B. (1994). Communication for Development and Social change. Allied Publishers.

If statistical tests are required, "One Group Pretest and Posttest Design" is the best design with "Paired Sample T-Test".

There are many variations of the before & after design. Do a literature search on REPEATED MEASURES, WITHIN SUBJECTS, DEPENDENT SAMPLES, SMALL SAMPLE DESIGNS, SINGLE SUBJECT DESIGNS.

The most important consideration is the confounding variables pertinent to your design given your topic. A major factor in longitudinal research on the lifespan is subject attrition. A major factor in psychiatric treatment is the natural course of the disorder (e.g., depression cases tend to remit over time, dementia cases tend to worsen over time).

The inferential statistics I use most often for these designs would be Wilcoxon test for two measures or the Friedman test for three or more measures. If your sample size is only one subject, and you are using many measures of the dependent variable (e.g., every day for a month), use a Mann-Whitney and compare the "group" of before scores with the "group" of after scores. Also analyze for trends by plotting the line graph.

Thank you very much for your precious comments. I would appreciate if someone refers some good quality articles related to this technique.