Comments on: Likert scale & surveys - best practices

By: Glenn

Glenn — Mon, 30 Jun 2008 08:31:36 +0000

Many thanks for those comments John & Donny. From what I’ve read, studies show there is little difference in reliability in using 5 or 7 point scales - studies on the whole tend to favour 5 over 7 - but not all agree. Most agree that more than 7 point scales are difficult for respondents to handle. Personally, I use 5 point scales often in surveys as I find 3 points too little and 7 points too many.
Glenn

By: John Dawes

John Dawes — Mon, 30 Jun 2008 07:10:31 +0000

I recently published a study that used a ’split sample’ experiment to see if the number of scale points has any effect on survey data. I split respondents into three groups, one answered using a 5-point scale, another group used a 7-point scale and the third, answered using a 10-point scale. I “re-scaled” the data using a simple bit of arithmetic, and the three scales produced almost identical results in terms of mean scores and variation about the mean. If anyone would like to look at a draft copy of the study, and does not have access to the journal, you can email me. Otherwise, the reference is Dawes, John. “Do Data Characteristics Change According to the Number of Scale Points Used ?” International Journal of Market Research Vol 50, No.1, 2008.

By: donny

donny — Sat, 28 Jun 2008 09:47:55 +0000

hi glenn,i’m doing my final assignment now about service quality in a retail store. i’m little bit confuse about using likert scale. I’m confuse whether to use 5 or 7 Likert scale.
Can you mention some advantages and disadvantages of both 5 and 7 likert scale?
thx before..

By: Ruby

Ruby — Fri, 06 Jun 2008 12:00:30 +0000

Could you please help me out with the advantages of using a four point likert scale as opposed to using the five point one.

By: rachana

rachana — Fri, 30 May 2008 05:36:39 +0000

Hi ,your article help me a lot in my market research first step. i need your immediate help for my research.i want to learn all the interpretation of factor and cluster analysis.this is my humble request to you.and i hope you will definitely help me.
Thanks.

By: Glenn

Glenn — Tue, 20 May 2008 13:13:10 +0000

Hello Kisha,

I am not sure you will be able to find a survey that precisely matches the one of your dissertation, but you can certainly check the scales you use with scales used by others:

http://www.gifted.uconn.edu/siegle/research/Instrument%20Reliability%20and%20Validity/Likert.html

http://dataguru.org/ref/survey/responseoptions.asp

Glenn

By: Kisha

Kisha — Mon, 19 May 2008 20:56:47 +0000

I am completing my dissertation. I was told I would have better success if I found a survey comprable to the one I am attempting to create. Does anyone know of a site that provides a listing of various Likert scale surveys?

By: Glenn

Glenn — Sun, 13 Apr 2008 13:37:52 +0000

Dear Harry,

Apologies, I just saw your comment now. Actually most studies are not conclusive on the difference between 5 and 7 points on a scale. In other words, both 5 & 7 point would provide you with accurate and reliable responses. In the article listed below, they conclude that as you add more points, a scale becomes more reliable - but only up to a certain point (higher than 11 is too much for most people). Consequently, they argue that 7 is slightly more reliable than 5.

I would recommend that you use a 7 point scale, particularly if you have other comparative variables that you are going to measure on a 7 point scale - it makes it much easier to compare and avoids having to re-calculate your results.

The article I mentioned:

Alwin, D & Krosnick, J, “The reliability of survey attitude measurement: The influence of questions and respondent attributes”, Sociological Methods Research, 1991; 20; 139
http://smr.sagepub.com/cgi/content/abstract/20/1/139

Kind regards,

Glenn

By: Glenn

Glenn — Sun, 13 Apr 2008 13:26:43 +0000

Dian, further to your question, actually some questions are more suited to a yes/no response and others are more suited to a Likert scale. For example, “have you ever done XY?” is suitable for yes/no. but “how favourable are you for XY?” is more suitable for likert style format. The likert scale is more for where you can imagine responses on a scale of frequency/intensity. For some questions this may not be appropriate.

I think if you are working with questioners doing the surveying for you, then you just have to guide them further with the response model written on your survey.
Glenn

By: Glenn

Glenn — Sun, 13 Apr 2008 13:02:03 +0000

HI Dian,

That’s a good one also! let me think about that I’ll get back to you…
Glenn