**Step 1**: First look at the**type of variable**. Is it quantitative or is it qualitative variable?- Quantitative variable: Can be measured and expressed as ‘mean’ (Ex: Number of children, Height, Weight, mean Hb% etc.)
- Qualitative variable: Cannot be measured but expressed in ‘proportion’ (Ex: Blood group, Severity of anemia, Prevalence of obesity etc.).

**Step 2**: See**how many groups**are discussed in the question. It may be:- Comparison between 2 groups
- Comparison within 1 group: before & after an intervention.

- Step 3: Give the answer by following the table:

### Tips to remember:

- ‘Quanti’ contains 1
**T**: So, in ‘Quanti’ variables:**T**test to be done- If done between 2 groups: the test of choice is Student’s T test (as the word ‘S
**T**UDEN**T**‘ contains 2T) - If done among >2 groups: test of choice is ANOVA (Remember: QU
**AN**TITATI**V**E –**AN**O**V**A)

- If done between 2 groups: the test of choice is Student’s T test (as the word ‘S
- If variable is qualitative and done between 2 groups: the test of choice is Chi-Square as ‘Square’ means 2nd power.

**Example 1:**

The prevalence of DM was 20% in a population. After an awareness campaign of impact of diet on DM, it came down to 13%. Which test of significance should be used?

- Chi-Square test
**McNemar test**- Student’s T test
- Paired T test.

Explanation:

- Step 1: Type of variable: Prevalence of DM: Qualitative variable
- Step 2: Only 1 group: Before & after an intervention
- Step 3: So, the test of choice is McNemar test.

**Example 2:**

Mean Hb level in a group of adolescent women was 9.2 gm%. After iron & folic acid tablet supplementation, it goes to 9.6 gm%. Which test of significance should be used?

- Chi-Square test
- McNemar test
- Student’s T test
**Paired T test**.

Explanation:

- Step 1: Type of variable: Mean Hb levele: Quan
**t**i-tative variable (**T**test) - Step 2: Only 1 group: Before & after an intervention
- Step 3: So, the test of choice is Paired T test.

**Example 3:**

Mean Hb level in 3 groups of adolescent women was 9.2 gm%. After iron & folic acid tablet supplementation, it goes to 9.6 gm%. Which test of significance should be used?

- Chi-Square test
- Student’s T test
- Paired T test
**ANOVA test**.

Explanation:

- Step 1: Type of variable: Mean Hb levele: Quantitative variable
- Step 2: 3 groups involved
- Step 3: So, the test of choice is ANOVA test (QU
**AN**TITATI**V**E –**AN**O**V**A).

Please re-check example 3.

Great initiative