Date:         Fri, 9 Feb 2007 16:41:50 -0500
Reply-To:     Richard Ristow <wrristow@mindspring.com>
Sender:       "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From:         Richard Ristow <wrristow@mindspring.com>
Subject:      Re: Mass Reverse scoring
Comments: To: Mark Webb <targetlk@iafrica.com>
Comments: cc: Natasha Kruse <nkruse88@YAHOO.COM>
In-Reply-To:  <001901c74c0c$4e67c310$0400000a@Work>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 12:36 AM 2/9/2007, Mark Webb wrote:

By the way, if you have a 5-point scale named MY_ITEM, the reverse of
it is
COMPUTE REV_ITEM = 6 - MY_ITEM.

But if you have user-missing values, you don't want to change them, so
you should use RECODE instead.

>Try recode in same variables or recode into new variables depending on
>your needs.

I was going to say, never do the former, because it's totally
confusing: there's no way to tell that the variables' coding has been
reversed, you'll forget whether you've done it...

I recently worked on a small study, following that advice. For
questions that were reverse-coded, we created scratch variables with
the coding reversed accordingly, and used the reversed versions in
calculating scales.

But on a bigger study finished about a year ago, I did recode
reverse-coded questions 'in place' - recoded the original variables.

The survey had 60 forward-coded and 38 reverse-coded questions, and a
great many scales. (Likely too many, but that's another question.)
Remembering when to enter to original variables and when to enter
reverse-coded forms seemed even more error-prone than recoding the
original variables.

But it took a lot of precautions to feel comfortable doing it:

. There was a very clear data path from one stage of processing the
data to the next. It was very clear, and clearly documented, at which
stage the reverse-coded variables had been recoded.

. Variable labels identified forward- and reverse-coded questions:
    s02q01   '-- Everybody knows who's on the team'
    s02q02   'RV Great uncertainty about team goal'

. Value labels were changed to match the recoding for reverse-coded
questions, so at least a FREQUENCIES would be clear:
   5 ' 1.Very Inaccurate'
   4 ' 2.Smwt Inaccurate'
   3 ' 3.Nthr.Acc/Inacc '
   2 ' 4.Smwt Accurate  '
   1 ' 5.Very Accurate  '
   8 ' 8.NA             '
   9 ' 9.BLANK          '
(Note that the label gives the number originally selected on the
questionnaire; the value is the value into which it's been recoded.)