1. Typographical Errors: Simple keystroke mistakes can alter data values, such as entering "55" instead of "5". 2. Misclassification: Incorrectly categorizing data, such as listing a patient with a non-communicable disease under infectious diseases. 3. Omission Errors: Failing to enter data points, leading to incomplete datasets. 4. Duplication: Entering the same data point multiple times, which can skew results. 5. Transcription Errors: Mistakes made while manually copying data from one source to another.
