How to report descriptive statistics in APA 7
Descriptive statistics provide the scale and spread readers need before they interpret inferential tests. A compact APA presentation gives the mean and standard deviation together: M = value, SD = value. Both abbreviations are Latin-letter statistical symbols and are italicized. Means and standard deviations can exceed 1, so retain their leading zeros. Two decimal places are a useful default, although the precision should match the measure and the conventions in your field.
The sample size can be added as N for a total sample or n for a subgroup. Use a whole number and keep the symbol italicized. A range may be useful when minimum and maximum values reveal the observed scale; this formatter places the two values in square brackets, separated by a comma. Common mistakes include writing "SD" without italics, giving a negative standard deviation, reporting inconsistent decimal precision, or presenting a bare mean without enough information about variability. Unlike p and correlations, descriptive values usually keep the leading zero. If the variable itself is constrained between 0 and 1, preserve precision appropriate to that scale rather than mechanically removing the zero.
Worked example
A sample of 128 respondents had a mean score of 42.36, a standard deviation of 7.84, and observed scores from 18 to 60.
N = 128, M = 42.36, SD = 7.84, range = [18.00, 60.00].
Common questions
Which symbols are italicized?
M, SD, N and n are Latin-letter statistical symbols and are italicized.
Do means and standard deviations get a leading zero?
Usually yes, because they can exceed 1. If the variable itself is bounded between 0 and 1, keep precision appropriate to that scale rather than mechanically removing the zero.
How many decimals should I report?
Two decimal places is a useful default, but match the measure and the conventions in your field.
When do I use N and when n?
Use N for the total sample and n for a subgroup, as a whole number.
How do I format a range?
This formatter puts the minimum and maximum in square brackets, separated by a comma, as in range = [18.00, 60.00].