Survey Data Quality in India: A Researcher's Checklist to Catch Careless, Duplicate and Fake Responses

Survey data quality checklist for Indian online studies: speeders, straight-lining, attention checks, open-ends, duplicates and a data-cleaning rule set.

In shortData quality checks look for three problems: careless respondents (speeding, straight-lining, nonsense open-ends), duplicates and fraud. Build checks into the questionnaire, decide cleaning rules before fieldwork, combine several flags and report what you removed. AAPOR says no widely accepted cleaning standard exists. Hercules Works documents automatic attention checks, speeder and straight-lining flags, open-end scoring and deduplication on its panel.

Survey Data Quality in India: A Researcher's Checklist to Catch Careless, Duplicate and Fake Responses
Contents

Bad Responses Do Not Look Bad in a Bar Chart

A careless or fake response still gives a valid-looking answer to every question. Once it is averaged into a total, nothing marks it out. The only place to catch it is the respondent-level file, before analysis.

On our panel, the answers come from real people. Member profile data (age band, gender, city, NCCS, segments) comes from profiling the existing user base, and the survey responses are collected from those members, not generated, modelled or bought.\n\nThis guide is a checklist. First comes what the industry bodies say, then what to build into the questionnaire, how each check works and fails, a worked speed calculation, a set of data-cleaning rules you can apply to any survey export, and the questions to put to any panel provider.

What AAPOR, ESOMAR and ISO 20252 Say

AAPOR. The 2010 AAPOR task force report on online panels lists the behaviours linked to satisficing: "response non-differentiation ('straightlining'), random responding, responding more quickly than would be expected" (speeding), response order effects and heavy use of "don't know". It also states that "there is no widely accepted industry standard for editing and cleaning panel data" (AAPOR Report on Online Panels, Public Opinion Quarterly, 2010).

ESOMAR. The 2012 edition of its 28 Questions to Help Buyers of Online Samples (September 2012) asks every provider who is responsible for data quality checks and whether there are procedures against "random responding", "illogical or inconsistent responding", "overuse of item non-response" and "speeding". Question 22 asks about "a confirmation of respondent identity procedure" and procedures "to detect fraudulent respondents" (ESOMAR, 2012 edition). ESOMAR also lists a later 37 Questions to Help Buyers of Online Samples, so check the current edition as well.

ISO 20252. BSI's listing of the 2019 edition says the standard "establishes terms, definitions and service requirements for service providers" and "now also covers access panels, both online and offline" (BSI). Research Live reported on 1 September 2026 that it has been updated as ISO 20252:2026, including "strengthening data quality requirements in sampling and panel management" (Research Live). The full text is sold, so ask a provider which edition it is certified to and for which methods.

Build the Checks Into the Questionnaire

You cannot clean what you did not measure. Add these before fieldwork. The numbers are our suggestions, not standards.

  1. Attention checks. Put in about one per seven questions, with instructions such as "select the animal" or "select the colour". Rotate the position and keep them short.
  2. A reverse-worded item in every grid you plan to check, so a flat line is also a contradiction.
  3. One bogus item. For a phone survey: "I have never used a mobile phone".
  4. An invented brand in each brand-awareness or purchase list.
  5. A neutral screener. Ask the category question among decoys, with an explicit time frame such as "in the last three months". Never hint at the answer that qualifies.
  6. A re-check of key eligibility later in the survey, in different words.
  7. At least two open-ended questions, so one weak answer is not the only evidence.
  8. Exclusion windows. Agree how long a member is kept out of repeat invitations on the same topic.

Attention checks alone are weak, as below. Use them as one flag among several.

Speeding: A Worked Relative Speed Index

Dominik Leiner tested several indicators in four studies and found that "careless responses are most reliably identified by questionnaire completion time" (Leiner, Survey Research Methods, 2019). His relative speed index works page by page. For each page, divide the sample's median time by the respondent's time. A factor of 2 means twice as fast as typical. Cap each page factor at 3, then average across pages.

PageMedian time (s)Respondent A (s)A factorRespondent B (s)B factor
140152.67351.14
260203.00700.86
330122.50251.20
490303.00801.13
550202.50103.00 (capped from 5.00)
Average2.731.47

Leiner suggests "a much more lenient cut-off of 2.0 to identify particularly suspicious records". Respondent A is above it. B, who rushed one page, is not. He adds a limit: if the questionnaire asks for facts or knowledge rather than opinions, completion time is not a valid indicator, because experts answer faster.

Straight-Lining, Attention Checks and Bogus Items

AAPOR describes straight-lining as "selecting the same response for all items in a grid" and notes that it "could also indicate a poorly designed questionnaire". Someone who agrees with both "Price matters most to me" and "I never look at the price" has given you a contradiction, not just a flat line.

Trap questions are less reliable than they look. In Pew Research Center's 2019 tests of opt-in samples, "some 84% of bogus respondents pass the trap question and 87% pass a check for responding too quickly" (Pew, February 2020). Leiner makes the same point: a respondent making up coherent answers "will likely pass attention checks". Bogus items worked better in his data, though he notes they were used in only one sub-sample. His examples include "I'm currently filling out a questionnaire" and "I have never ever used a computer".

Open-Ended Answers, Duplicates, Screeners and Fraud

Open-ends. AAPOR suggests looking for "gibberish or answers that appear to be copied and then repeatedly pasted in question after question". Pew found that 2% to 4% of opt-in respondents "repeatedly gave answers that did not match the question asked", against 0% in address-recruited panels. Read answers in the language they were written in. A short Hinglish answer such as "price thoda zyada hai" is a valid answer, not low effort.

Duplicates. AAPOR says the most common technique is digital fingerprinting, which builds an ID from IP address, browser and device settings. It warns that "false positives are possible (e.g., two persons in the same household)", so review flagged pairs before deleting. Where a household shares one phone, compare the two records' age, gender and answers first.

Screener integrity and fraud. Fakers try to qualify. AAPOR notes researchers "may include false brands, nonexistent products, or low-incidence behaviors" in screening questions. A respondent who claims to buy your invented brand regularly is not a real category buyer.

Data-Cleaning Rules You Can Apply to Any Survey Export

Write these rules into the analysis plan before fieldwork, so nobody tunes them to get a preferred result. Only rule 1 comes from a published source. The other thresholds are our suggestions, built on the AAPOR and Leiner material above. They are not benchmarks, so adapt them to your questionnaire. Every check removes some honest people and misses some bad ones, which is why AAPOR notes some researchers use "a scoring system in which a case must fail on multiple tests before it is eliminated". Rule 12 does that.

#RuleOur suggested thresholdAction
1Relative speedMean speed index above 2.0 (Leiner's cut-off; opinion questions only)Remove
2Total timeUnder one third of the median completeSoft flag
3Straight-liningSame answer on every item in two or more grids of five or more itemsSoft flag
4Attention checksFails one checkSoft flag
5Attention checksFails two or more checksRemove
6Bogus itemAgrees with "I have never used a mobile phone"Remove
7Invented brandClaims regular purchase of a brand that does not existRemove
8Open-endsGibberish, pasted repeats or off-topic in two or more open questionsSoft flag
9Screener consistencyEligibility answer contradicts the same criterion asked in other wordsRemove
10"Don't know"On more than half of the itemsSoft flag
11DuplicatesSame device ID and matching age band, gender and city; review the pair firstKeep the first complete, remove the other
12Combined soft flagsTwo or more of rules 2, 3, 4, 8, 10Remove

Worked example (made-up file). A study returns 1,000 completes. Rule 1 removes 38. Rules 6, 7 and 9 together remove 7. Review of 6 duplicate pairs confirms 4. Among the rest, 10 respondents carry two or more soft flags. No record is counted twice, so 38 + 7 + 4 + 10 = 59 records out and 941 analysed. Report all four numbers, and compare the key results with and without the removed cases. If the headline finding moves, say so.

Verifying the Numbers in the Report

Clean data can still produce a wrong chart. Take three or four headline figures and recompute them from the respondent-level file yourself. Check the base for each figure: all respondents, or only those shown the question after skip logic? Check that single-choice answers sum to 100% and that multi-select charts say respondents could pick more than one. Check that any weighting in the method note was applied. Fix anything you find before the report goes out.

Questions to Ask Any Panel Provider

These follow ESOMAR's buyer questions and AAPOR's advice that a researcher should confirm a panel has removed multiple identities before using it.

  1. How is each member's identity confirmed when they join, and how do you detect fraudulent respondents?
  2. Which in-survey checks run automatically, and what are the rules?
  3. Are removed responses visible to me, with the reason for each?
  4. How often can one person take part in surveys in a given period, and can the exclusion window be set per study?
  5. Can I get respondent-level data, including completion times?
  6. Do you review questionnaires for quality before they go live?
  7. Are you certified to ISO 20252, which edition, and for which methods?

Running This Study on Hercules

If your job is a consumer survey in India, here is what our platform documents against the checklist above. These are capabilities, not guarantees, and we do not publish the thresholds or removal rates behind them.

  • Attention checks inserted automatically, about one per seven questions.
  • Flags for speeders and straight-lining.
  • Open-end scoring for gibberish, copy-paste and off-topic answers.
  • Panel deduplication, with configurable exclusion windows.
  • Screener integrity: neutral category screens among decoys, explicit time frames, a red-herring brand, and key criteria re-checked in other words.
  • A 9-dimension quality rubric with hard gates, which blocks a weak survey from publishing.

Members of the SuperJ app complete Aadhaar-based KYC once, then take part through a zero-knowledge proof, so researchers get verified answers without identity data. The app has a 25M+ consumer footprint; the survey-eligible panel is a subset and depends on your targeting. Surveys run in as many Indian languages as the study needs (panel methodology). Keep your own duplicate review in place. A 500-complete study costs 500 × ₹120 = ₹60,000 on a Pro bundle (pricing), and the Free plan includes 30 responses for a trial file. The limit: the panel is India only and app-based, so offline households need face-to-face fieldwork.

Start free with 30 responses

Frequently asked questions

What is a speeder in a survey?

A respondent who finishes much faster than reading the questions would allow. One published rule, Leiner's relative speed index, flags people who are on average more than twice as fast as the median respondent, page by page.

What is straight-lining?

Giving the same answer to every item in a grid. It can signal low effort, but AAPOR notes it can also come from a poorly designed grid, so include a reverse-worded item before using it as a removal rule.

How many attention checks should a survey have?

Our suggestion is about one per seven questions, kept short and placed at different points. Treat them as one flag among several, because Pew found 84% of the bogus respondents it identified passed its trap question.

Is there a standard for survey data cleaning?

AAPOR's 2010 report says there is no widely accepted industry standard for editing and cleaning panel data. ISO 20252 sets service requirements for research providers, and ESOMAR lists the quality questions a buyer should ask.

How many responses should I expect to remove?

It depends on the source, the questionnaire and your rules, so set the rules first and report what they remove. Pew's 2019 tests found about 4% to 7% bogus respondents in opt-in sources and about 1% in two address-recruited panels.

How do I detect duplicate respondents?

Digital fingerprinting of the device and browser is the most common method AAPOR describes. Review flagged pairs before deleting, because two people in one household can share a device.

Do the cleaning thresholds in this guide apply to every survey?

No. Only the 2.0 speed cut-off comes from a published source, and it applies to opinion questions. The rest are our suggestions. Test them on a pilot file and write the final rules into your analysis plan.

Sources and further reading

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