Sample Size Calculator: Guided Selection

Please answer two simple questions about your research to find the correct sample size calculation method.

1. What type of Outcome Variable is your research focusing on?

The outcome variable (or dependent variable) is the result you are measuring.

1. Qualitative / Categorical Variable e.g., Blood Group, Gender, Presence/Absence of a disease (Data expressed as **Proportions**). 2. Quantitative / Numerical Variable e.g., Blood Pressure (mmHg), Weight (kg), Age (years) (Data expressed as **Means**).

2. What is the Primary Objective of your research? (Qualitative Data)

1. **Estimation:** To determine the prevalence of a condition in a single group. 2. **Hypothesis Testing:** To test the difference in proportions between two groups.

3. What is the Primary Objective of your research? (Quantitative Data)

1. **Estimation:** To determine the average (mean) of a variable in a single group. 2. **Hypothesis Testing:** To test the difference in means between two groups.

Calculation Selected:

Go to Calculator

Sample Size Calculator: Guided Selection

1. What type of **Outcome Variable** is your research focusing on?

2. What is the **Primary Objective** of your research? (Qualitative Data)

3. What is the **Primary Objective** of your research? (Quantitative Data)

1. What type of Outcome Variable is your research focusing on?

2. What is the Primary Objective of your research? (Qualitative Data)

3. What is the Primary Objective of your research? (Quantitative Data)