From tiny cohorts to national benchmarks, these are the traps that can turn useful exam data into misleading conclusions.
Exam-results data can produce useful questions very quickly.
It can also produce misleading conclusions very quickly.
Here are ten traps worth checking before finalising a departmental results report.
Grade 4+ or A*–B may be important, but neither describes the complete distribution.
Better: examine several thresholds and individual grades.
A ten-percentage-point movement may represent one student.
Better: report numbers and percentages together.
National results describe a national cohort with a different mix of students.
Better: use national data as a benchmark and source of questions.
A movement from 20% to 25% is five percentage points, but a 25% relative increase.
Better: use percentage points when comparing attainment rates.
Two cohorts are not enough to establish a reliable pattern.
Better: look across several examination years where possible.
GCSE all-age results, for example, may include resit candidates as well as Year 11 students.
Better: check exactly who is represented in the national figures.
“Weaker Paper 2 results” does not prove that Paper 2 was taught badly.
Better: treat the result as a question and gather more evidence.
A stable grade 4+ rate could disguise large changes at grades 7–9 or grades 1–3.
Better: inspect the full distribution.
Results analysis should identify successful practice too.
Better: ask what should be maintained as well as what should change.
A long action plan can give the illusion of rigour while making improvement less likely.
Better: identify a small number of priorities with clear evidence behind them.
Before sharing your analysis, ask:
What do the data definitely show?
What are we inferring?
What additional evidence would test that inference?
What action is genuinely justified?
If those four questions are clear, the analysis is probably doing its job.
Use the tutor2u Exam Results Explorer to benchmark your own GCSE or A-Level grade distribution against national data.
Last checked August 2026. This is a plain-English summary of official guidance; always check the linked Ofqual, JCQ and exam-board pages for the definitive rules, which can change.
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