Case study is an in-depth, intensive investigation of a single individual, a small group or an institution. The researcher collects detailed information about the person's present condition, history, family, school, health and environment through interviews, observation, tests, records and reports of relatives. It is mostly used in clinical and counselling work, for example to study a child with severe behaviour problems or a person with a rare disorder.

Merits

1. It gives detailed, deep and comprehensive information about the individual.
2. It studies the person in a natural, real-life setting and considers past as well as present.
3. It is useful for studying rare or unusual cases (for example a brain injury) that cannot be created in a laboratory.
4. It helps in diagnosing the cause of a problem and planning treatment or counselling.
5. It can suggest hypotheses for later research.
6. Many sources of information are used, so the picture is rich and flexible.

Demerits

1. Results cannot be generalised, because only one or a few cases are studied.
2. It is time-consuming and costly.
3. It depends on memory of the person and relatives, which may be inaccurate or biased (retrospective error).
4. The researcher may be subjective and interpret information according to personal opinion.
5. Cause and effect relationships cannot be established with certainty.
6. The person may hide information or behave artificially, and privacy and ethical issues arise.

In conclusion, the case study method is valuable for deep understanding of individuals, but its findings should be supported by other methods before being applied widely.

Descriptive research is a type of research that describes the characteristics, behaviours, or conditions of a group or situation as they exist, without manipulating any variable. It answers what, who, when, and how questions rather than why. The survey method is the most widely used technique of descriptive research.

Illustration of descriptive research through the survey method:

1. Purpose and nature. Suppose a researcher wants to describe the study habits of Class 11 students in Kathmandu. The aim is only to describe the existing pattern of study habits — not to test a cause–effect relationship. This is descriptive research.

2. Selection of sample. The researcher defines the population (all Class 11 students in Kathmandu) and draws a representative sample, say 300 students, using random or stratified random sampling. Representativeness is essential because conclusions are generalised to the whole population.

3. Preparation of tools. A structured questionnaire or interview schedule is prepared with clear, unbiased questions on study time, place of study, use of mobile phones, tuition, and examination preparation. Closed-ended items (e.g., Likert-type scales) make scoring and comparison easy.

4. Collection of data. Data are collected by administering the questionnaire to students in their schools or through interviews, online forms, or telephone. Standardised instructions are given so that all respondents answer under similar conditions.

5. Analysis of data. Responses are scored and analysed using descriptive statistics — frequencies, percentages, means, and standard deviations. Tables, bar diagrams, and pie charts are used to present the findings.

6. Interpretation and reporting. The researcher describes, for example, that 60% of students study 2–3 hours daily and that most prefer morning study. Generalisations are drawn about the population, and limitations (e.g., honesty of responses, sampling bias) are stated.

Conclusion. Thus, the survey method illustrates descriptive research by systematically collecting data from a representative sample through questionnaires or interviews and describing the existing characteristics of a group without any manipulation of variables. It is economical, covers a large population, and yields generalisable facts — though it cannot explain the causes behind the described behaviour.

Steps Needed to Study the Psychological Effects of COVID-19 Among School Students

Studying the psychological effects of COVID-19 among school students is a systematic research problem. It must follow the scientific method, which involves a series of orderly steps from identifying the problem to reporting the findings. The major steps are described below.

1. Identifying and Defining the Problem

The researcher first identifies a clear and specific problem: What are the psychological effects of COVID-19 among school students? The problem is then defined in clear, measurable terms — for example, effects on anxiety, depression, stress, fear, sleep, concentration, and social behaviour. The scope (age group, class level, locality, time period) is also specified.

2. Reviewing Related Literature

The researcher studies previous research, articles, reports (e.g., WHO, UNICEF), and theories related to pandemics and mental health. This helps in understanding what is already known, avoiding repetition, and identifying the gap the present study will fill.

3. Formulating Objectives and Hypotheses

Clear objectives are stated, such as:

• To find the level of anxiety and stress among school students during COVID-19.
• To compare effects between boys and girls, or between rural and urban students.

On this basis, testable hypotheses are formed, e.g., "There is a significant difference in anxiety levels between boys and girls during COVID-19."

4. Selecting the Research Design

An appropriate design is chosen. For this topic, a descriptive survey design (cross-sectional) is most suitable, since the aim is to describe the existing psychological condition of a large group. A correlational or comparative design may be added to study relationships or group differences.

5. Defining the Population and Sample

• Population: All school students of a given area (e.g., Kathmandu Valley, or Nepal).
• Sample: A representative subgroup selected through probability sampling (simple random, stratified by grade/gender/location) or, if difficult, purposive sampling. The sample size should be adequate (e.g., 200–500 students) for reliable results.

6. Selecting and Constructing Tools

Standardized tools are preferred, such as:

• Anxiety scales (e.g., Beck Anxiety Inventory, Spence Children's Anxiety Scale)
• Depression scales (e.g., PHQ-A, CES-DC)
• Stress scales (e.g., Perceived Stress Scale)
• Self-made questionnaires on online classes, isolation, family conflict, and screen time

Tools must be valid (measuring what they claim) and reliable (giving consistent results). A pilot study on a small group helps refine them.

7. Collecting the Data

Data may be collected through:

• Questionnaires (online Google Forms or printed)
• Interviews with students, parents, and teachers
• Observation of behaviour and participation
• School records (attendance, counselling cases)

Ethical considerations must be followed: informed consent from parents/guardians, assent from students, confidentiality, anonymity, and the right to withdraw.

8. Organizing and Analyzing the Data

Collected data are scored, tabulated, and analyzed using:

• Descriptive statistics — mean, median, standard deviation, percentages, graphs
• Inferential statistics — t-test, chi-square, correlation, or ANOVA to test hypotheses

Qualitative data from interviews are analyzed by identifying themes (e.g., fear of infection, loneliness, academic pressure).

9. Interpreting and Drawing Conclusions

The results are interpreted in light of the objectives and hypotheses. The researcher explains whether the findings support the hypotheses, compares them with previous studies, and states the conclusions — for example, whether COVID-19 significantly increased anxiety and reduced social interaction among students.

10. Reporting the Findings

Finally, the researcher prepares a research report containing the title, objectives, methodology, results, discussion, conclusion, and suggestions. The report may be submitted to the school, published, or used to recommend counselling services and mental-health support programmes for students.

Conclusion

Thus, studying the psychological effects of COVID-19 among school students requires a stepwise scientific approach — from problem identification and literature review, through hypothesis formation, sampling, tool construction, data collection, analysis, and interpretation, to the final report. Following these steps ensures that the findings are valid, reliable, and useful for the welfare of students.