Development of Knowledge Test
A knowledge test is a tool used to measure the factual information, understanding, and awareness of respondents about a particular subject, innovation, or practice (e.g., farmers’ knowledge about Integrated Pest Management, soil conservation, or dairy practices).
It must be valid, reliable, and objective.
Steps in Developing a Knowledge Test
- Planning the Test
- Define the objectives: What do you want to measure? (e.g., knowledge of farmers on organic farming).
- Specify the content area: List the important units/topics/subtopics.
- Decide the type of knowledge:
- Factual knowledge (facts, terms, definitions).
- Comprehension (understanding of principles, concepts).
- Application knowledge (ability to apply knowledge in practical situations).
- Collection of Items (Question Pool)
- Prepare a large pool of items (statements/questions) covering the full content area.
- Items can be:
- Multiple-choice questions (MCQs)
- True/False statements
- Fill-in-the-blanks
- Matching type
- Ensure items are simple, unambiguous, and relevant.
Example:
- IPM includes both chemical and non-chemical methods. (True/False)
- Which of the following is a bio-control agent? (Options…)
- Editing of Items
- Remove ambiguous, vague, or overlapping items.
- Ensure language is simple and free from technical jargon.
- Each item should test one aspect of knowledge only.
- Pre-Testing / Item Analysis
- Administer the draft test to a small representative sample of respondents (pilot testing).
- Analyze each item using:
- Difficulty Index (P): % of respondents answering correctly. Ideal range: 20–80% (neither too easy nor too difficult).
- Discrimination Index (D): Ability of an item to discriminate between high and low scorers. Good items: D ≥ 0.30.
- Point-biserial correlation (rpbis): Correlation of item score with total test score. Accept items with rpbis ≥ 0.20.
- Selection of Final Items
- Retain items that fall within acceptable difficulty and discrimination ranges.
- Discard weak items.
- Ensure content coverage and balance.
- Administration of Final Test
- Prepare instructions for respondents.
- Ensure standardized administration (same procedure for all).
- Decide scoring pattern (1 mark for correct, 0 for wrong/blank).
- Establishing Reliability
- Reliability = Consistency of the test results.
- Methods:
- Split-half reliability (test divided into two halves, scores correlated).
- Test-retest method (administer twice, correlate scores).
- Kuder-Richardson formula (KR-20/21) for dichotomous items.
- Acceptable reliability: ≥ 0.70.
- Establishing Validity
- Validity = Does the test measure what it is supposed to measure?
- Types:
- Content validity (adequate coverage of subject matter).
- Construct validity (logical structure of the test).
- Criterion-related validity (correlation with external criterion, e.g., experts’ ratings).
- Standardization of the Test
- Prepare the final test with instructions, scoring key, and interpretation guidelines.
- Document procedure for administration, scoring, and interpretation.
Characteristics of a Good Knowledge Test
- Validity – measures intended knowledge accurately.
- Reliability – gives consistent results.
- Objectivity – free from personal bias.
- Usability – easy to administer and score.
- Discrimination – differentiates between knowledgeable and less knowledgeable respondents.
Example Application in Extension Education
- Measuring farmers’ knowledge on organic farming.
- Measuring students’ knowledge of ICT tools in extension.
- Assessing knowledge gain before and after training programs.