Research questionnaires come from your theoretical and conceptual model. A literature review will show you how other researchers develop their questionnaires based on the constructs they used. Also you need to test it out with experts to make sure it is understandable and the questionnaires measure what it is intended.

Hi Dhanuhska Pushpakumara, basically the questions have to be designed to capture those features that allow the higher discrimination between good and bad loan performance (concepts which need also to be defined). For example, in the of case marital status, married people tends to be less risky than single ones, but this depends also in the context and combination with other demographic variables. I would also add income, since this is the main repayment indicator in banking.

I work at a bank and I can provide additional support if needed.

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What is the goal of your research?

based on that you may construct your questions.

where is your conceptual model based on?

perhaps find some information from the supply chain finance community and or specialised banks

world bank might also be useful

.... and of course website ifc

Write a list of objectives. This should outline the kind of data you want to collect, as it will serve as the basis for choosing your questions. For example, you may want to know how customers feel about your new product, in which case your objectives may be to gauge customer responses to the product's price range, ease of use, durability and concept

Decide on a method of administration. You may opt to use face-to-face interviews, telephone interviews, web-based surveys or written questionnaires

Organize the survey questionnaire in a logical way.

• If your research questionnaire covers a range of topics, then group the questions into subjects.
• Downplay sensitive questions by grouping them with neutral questions, and by placing them toward the end of the survey, after a rapport has been established.

Provide respondents with the information they will need in order to effectively comply with the survey. In order to achieve the best results, questionnaire design should amply prepare respondents in the following ways:

• Explain the purpose of the survey questionnaire. When people understand the reasons behind a line of questioning, they are more likely to volunteer accurate personal information.
• Word questions effectively. Keep the following in mind:
• Comprehension. Use simple language and keep sentences as brief and concise as possible. Be sure to cover the what, where, who, when and why so that respondents are not lacking for pertinent information regarding their input.
• Answerability. Respondents should be able to provide accurate answers without having to do research. For example, people may not be able to tell you exactly how much money they spend eating out in an entire year, but they should be able to estimate what they spend eating out over the course of a week.

Read literature review. Find research Gap.

Based on that, formulate research questions in aligning with your research problem.

Questions have to both serve the research questions and allow you to know "who has replied to your questionnaires", meaning that you should be able to identify the type of people (gender, age, use of microfinance services....)

If you have a confusion while reading literatures, better you should map the literatures according your theme.

If still there is an ambiguity in formulating research questions, then go for pilot study from small strata in your group. Influencing factors can be considered to be the variables.

By regression, ignore the least.

Include others as a part of research.

Research questionnaires come from your theoretical and conceptual model. A literature review will show you how other researchers develop their questionnaires based on the constructs they used. Also you need to test it out with experts to make sure it is understandable and the questionnaires measure what it is intended.

Get a good textbook online or offline in marketing research, there are many of these available. A very detailed guide to questionnaire design is included in Churchill and Iacobucci, Marketing Research: Methodological Foundations. There are other similar books but this is very good indeed. Survey design should not be done in an adhoc way, you are likely to miss important aspects.

Lot's of very useful suggestions already here. If still confused, you can reach-out to me.

properly defined objectives and thorough literature review to identify variables help you to develop a questionnaire

Intensive research will support.

Chronically review related papers.

Find the correlation of next Updation.

Finally, you can get them, based on object oriented questions you can frame