What anonymisation can we use?
A non-exhaustive list of commonly used techniques is set out below:
a) Pseudonymisation: replacing personal identifiers (e.g., names) with other references (e.g., tags which are randomly generated)
b) Aggregation: displaying values as totals, so that none of the individual values which could identify an individual is shown
c) Replacement: replacing values or a subset of the values with a computed average or a number derived from the values
d) Data suppression: removing values (e.g., ethnicity) that are not required for the purpose
e) Data recoding or generalisation: banding or grouping of categories (e.g., Primary 3) into broader categories (e.g., primary)
f) Data shuffling: mixing up or replacing values with those of the same type so that the information looks similar but is unrelated to the actual details
g) Masking: removing certain details while preserving the look and feel of the data (e.g., replacing NRIC numbers with X)