Scientific working methods and task analysis: material interpretation, data evaluation and argumentation
Domain 8 is the method layer of the Abitur. Marks here are earned by choosing the right operator, using the material explicitly, and separating description from judgement. Even a perfect factual answer loses marks if it answers a different operator.
Operators and Anforderungsbereiche
AFB I (reproduce): nennen, beschreiben, zusammenfassen. AFB II (apply and reorganise): erklären, berechnen, analysieren, vergleichen, in einen Zusammenhang stellen. AFB III (evaluate and reflect): beurteilen, bewerten, Stellung nehmen, diskutieren, erörtern. The written paper commonly weights these around 30 % / 50 % / 20 %; check the wording of the task before writing and keep AFB III statements out of a reproduction sub-task.
Reading material critically
- Establish source type, author, date and interest (study, advertising, NGO report, statistics office).
- Separate data from interpretation; check units, reference base (per 100 g or per portion) and whether a baseline is given.
- Statistics: n, mean versus median, standard deviation, error bars, control group, significance. Correlation is not causation; consider confounders, selection bias and dose–response.
- Study hierarchy: meta-analysis and randomised controlled trials above cohort studies, case-control studies, cross-sectional surveys and case reports. For dietary intake, 24-hour recalls and food frequency questionnaires carry recall and underreporting bias; doubly labelled water is the reference method for energy expenditure.
Argumentation structure
Claim - evidence from the material - reasoning - limitation - conclusion. Cite the material ("Material 2 zeigt …"), weigh at least two criteria (for example health benefit versus cost and consumer acceptance), and name what would change your judgement.
Worked example
A cohort study of 20 000 adults reports a relative risk of 0.80 for high wholegrain intake, with a baseline risk of 5 %. The absolute risk falls from 5 % to 4 %, i.e. by one percentage point; the number needed to treat is 1/0.01 = 100 people eating high wholegrain diets to prevent one event. The relative figure of "20 % less risk" sounds larger than the absolute 1 percentage point. A full evaluation must add that the data are observational, self-reported and possibly confounded by overall lifestyle, so causality is plausible but unproven.
Traps
- Describing a chart when the operator asks for an evaluation.
- Using "Studien zeigen" without naming the material.
- Forgetting units or comparing percentages from different reference bases.
- Ending a Stellungnahme without a conclusion or without acknowledging a counterargument.