OM book glossary

This is the glossary for the book “Outcome measures and evaluation in counselling and psychotherapy” written by myself and Jo-anne Carlyle and available now from SAGE. I am over 430 entries now and still climbing though now (April 2026) I am concentrating more on harmonising, cleaning up and cross-linking existing entries than I am on adding new ones. Some glossary entries link to more detailed expansions of the topic in my Rblog and, at last, an increasing number now link with interactive online (“shiny”) apps.

You can see the alphabetical list of entries below which is a good place to browse, or you can use this search box.

Beware: the way the search orders the matches is to my mind bizarre so scroll down if what you typed isn’t first on the list, you may find something with exactly the title that is exactly the phrase you typed in to find is hidden down the list of suggestions.

If what you want is not there and you think it should be, contact me and tell me and I will put it on the (long!) list of entries to be added!

E

Eigenvalue

The only places you find this term, which means "own value" from German, is in…

Efficiency

One of the 3 E’s from the hugely influential monograph: Cochrane, A. L. (1972). Effectiveness…

Effectiveness

One of the 3 E's from the hugely influential monograph: Cochrane, A. L. (1972). Effectiveness…

Efficacy (part of the 3 Es)

My "three E's" are Efficacy, Effectiveness and Efficiency which were the central theme of a…

Ecological Momentary Assessment (EMA)

This refers to collection of data from participants at various times of day in their…

Exploratory factor analysis (EFA)

A statistical approach that hopes to simplify multivariate data, i.e. data where we have values…

EPO-1

A single item, five level, change/outcome measure proposed for adoption within the European Psychotherapy Consortium…

European Psychotherapy Consortium (EPoC)

A coalition/consortium arising out of the Society for Psychotherapy Research meeting in 2022 and formalised…

Exploratory data analysis (EDA)

A statistical approach, methodology, inspired by John Tukey. Tukey was something of a polymath…

EQ-5D-5L

Probably the dominant quality of life measure, distributed by Euroqol and free for non-commercial use…

More

Creation date lost, updated 19.v.24 to add the new BetterDocs “encyclopedia” listing of entries, tweaks 13.iv.26. Author CE; this page and all glossary contents are copyright to me so contact me if you want to quote from them (I’m sure I’ll agree!). That may change to a Creative Commons licence later when I am happier with the content.