1. Method of data
collection
D.A. Asir John Samuel, MPT (Neuro Paed),
Lecturer, Alva’s college of Physiotherapy,
Moodbidri
Dr.Asir John Samuel (PT), Lecturer, ACP
2. Types of data
• Primary data
• Secondary data
Dr.Asir John Samuel (PT), Lecturer, ACP
3. Primary Data collection methods
• Observation method
• Interview method
• Questionnaires
• Warranty cards
• Distributor or store audits
Dr.Asir John Samuel (PT), Lecturer, ACP
4. Primary Data collection methods
• Consumer panels
• Use of mechanical devices
• Projective techniques
Dr.Asir John Samuel (PT), Lecturer, ACP
5. Secondary data
• Reliability of data
• Suitability of data
• Adequacy of data
Dr.Asir John Samuel (PT), Lecturer, ACP
6. Selection of appropriate method
• Nature, scope and object of enquiry
• Availability of funds
• Time factor
• Precision required
Dr.Asir John Samuel (PT), Lecturer, ACP
7. Questionnaires
• Consists of no. of questions printed or typed
in definite order on a form or set of forms
• Respondents have to answer the questions on
their own
• Data is collected through mailing or
distributing the questionnaires
• Used in survey
Dr.Asir John Samuel (PT), Lecturer, ACP
8. 3 main aspects
• General form
• Question sequence
• Question formulation and wording
Dr.Asir John Samuel (PT), Lecturer, ACP
9. General form
• Structured/unstructured
• Closed (Y/N) or open (inviting free response)
• In pilot study unstructured then standardized
Dr.Asir John Samuel (PT), Lecturer, ACP
10. Question sequence
• Clear and smoothly-moving
• Easiest question being put in beginning
• Avoid question that put too great strain on
memory, personal character, wealth, etc
• General to more specific
Dr.Asir John Samuel (PT), Lecturer, ACP
11. Question formulation and wording
• Short and Easily understood
• Simple and convey only one thought at a time
• Concrete
• Can be dichotomous, multiple choice or open-
ended
Dr.Asir John Samuel (PT), Lecturer, ACP
12. Questionnaires - Merits
• Low cost even when sample size is large
• Free from bias of interviewer
• Respondent who are not easily approachable
can be reached conveniently
• More reliable
• Respondents have adequate time to answer
Dr.Asir John Samuel (PT), Lecturer, ACP
13. Questionnaires - Demerits
• Low rate of return of duly filled in
questionnaires
• Can be used only when respondents are
educated and cooperating
• There is inbuilt inflexibility
• Slowest of all
Dr.Asir John Samuel (PT), Lecturer, ACP
14. Questionnaires - Demerits
• Interpretation of omissions is difficult
• Control over the questionnaire may be lost
once it is sent
• Difficult to know whether willing respondents
are true representative
Dr.Asir John Samuel (PT), Lecturer, ACP
15. Schedules
• Performa containing a set of questions are
being filled in by the enumerators
• Explain aims and objectives, removes
difficulties
• Should have capacity to cross-examine in
order to find out truth
Dr.Asir John Samuel (PT), Lecturer, ACP
16. Differences
Questionnaires Schedules
• Filled by respondents • Filled by enumerators
• Cheap • More expensive
• Non-response is high • Low non-response
• Not always clear • Clear
• Very slow • Comparatively faster
Dr.Asir John Samuel (PT), Lecturer, ACP
17. Differences
Questionnaires Schedules
• Personal contact not • Personal contact
possible possible
• Only literate and
• Even illiterate
cooperative
• Small sample coverage
• Wider sample coverage
• Information collected is
• Collecting incomplete
complete and accurate
and wrong information
Dr.Asir John Samuel (PT), Lecturer, ACP