Your reliability output
Take these two numbers straight from your SPSS or R output.
Between 0 and 1. Paste the figure exactly as reported.
Used only to flag whether the estimate is stable.
—
Cronbach's alpha
.87
Checks
- Above the .70 floor—
- Below the .95 redundancy line—
- Enough items to interpret—
- Sample large enough to be stable—
How to report it
What alpha does and does not tell you
- It is not validity. A scale can be perfectly consistent and still measure the wrong thing. Alpha is about consistency only.
- It rises with item count. A 20-item scale reaches .80 more easily than a 4-item scale. Report the item count alongside it, always.
- Higher is not always better. Above .95 usually signals redundant items rather than an excellent instrument.
- Check reverse-coded items first. A surprisingly low alpha is most often a reverse-coded item that was never recoded.
- For SEM, report composite reliability too. Alpha assumes equal loadings across items; CR does not.
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