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Brief Mood Introspection Scale (BMIS):
rd
- ( Technical and Scoring Manual - By John D. Mayer and Rachael Cavallaro, 26 February, Edition)
- Part 1: Description of the Brief Mood Introspection Scale (BMIS) Contents
- What the BMIS Looks Like
- The Four Scale Scores
- Obtaining the BMIS
- Part 2. Four Ways to Implement the BMIS
- Overview and Issues
- Subtractive versus Reverse Scoring.
- Part 3. Recommended Scoring: The Reverse-Scoring Method
- Score the Pleasant-Unpleasant Scale
- Score the Arousal-Calm Mood Scale
- Scoring the BMIS for Positive-Tired Mood
- Scoring the BMIS for Negative-Relaxed Mood
- Subtractive Scoring Part 4. Calculating the Range of 4-Point and 7-Point Scales that Use Reverse and
- Worded (PW) and Negatively-Worded (NW) Items
- Calculating the Range of Scores for Reverse Scoring of the 4-Point Scale
- The case of the seven-point response scale...............................................................
- Calculating the Range of Scores for Subtractive Scoring
- The case of the 4-point response scale
- The case of the 7-point response scale
- Part 5. Translating Between 4- and 7-Point Scales When Item-Level Data is Available - Example.
- Conversions from the 7- to the 4-Point Scale
- Compatibility with the 2016 IBM Support Center Conception of Scale Translation
- Scoring Part 6. Converting between 7-Point and 4-Point Scales and/or Reverse and Subtractive
- Overview
- Converting between Scoring Methods (Reverse and Subtractive Scoring Methods)
- Step 1: Calculating the Ranges
- Step 2: Calculating the Ranges’ Midpoints and the Zero-Centered Values
- Step 3: Comparing the Zero-Centered Values
- Step 4. Formalizing the Above in General Formulae
- Converting between Response Scales (4-Point and 7-Point Response Scales)
- Converting between Response Scales and Scoring Methods
- Part 7. Key Summary Equations and Tables
- Equations Below) Key Numerical Properties of the 4- and 7-Point BMIS Scales (Needed to Use the Key
- The Equations for Converting Between Reverse and Subtractive Scoring Methods
- The Equations for Converting Between 4- and 7-Point Scale Values
- Method Values The Equations for Converting Between 4- and 7-Point Response Scale and Scoring
- References
Part 1: Description of the Brief Mood Introspection Scale (BMIS)
What the BMIS Looks Like Before you start, it is helpful to download a copy of the BMIS in PDF or WORD format). Figure 1 provides a reasonable facsimile of the scale. Note that the scale is composed of instructions, followed by a response scale that goes: XX, X, V and VV. This is the “Meddis” response scale (named after its originator). Meddis (see credit under Figure 1) demonstrated that the alternatives, used with the labels shown below, go some way toward eliciting a normally distributed response profile across the four choices. Figure 1. A copy of the BMIS Original scale as described in Mayer, J. D., & Gaschke, Y. N. (1988). The experience and meta-experience of mood. Journal of Personality and Social Psychology, 55 , 102-111. The Meddis response scale was discussed in Meddis, R. (1972). Bipolar factors in mood adjective checklists. British Journal of Social Clinical Psychology, 11, 178 - 184. The four-point Meddis response scale is coded as a four-point scale such that XX is set equal to 1, X to 2, V to 3 and VV to 4.
The Four Scale Scores Four subscores can be computed from the BMIS: Pleasant Unpleasant, Arousal-Calm, Positive-Tired and Negative-Relaxed Mood. Each score is computed from a different scale (set of items) containing a different number of items, as indicated in Table 1.1. Pleasant-Unpleasant uses all 16 items, Arousal-Calm, 12 items, Positive-Tired, 7-items, and Negative-Relaxed, 6 items. Table 1. The BMIS items and the scales they fall on. The Four BMIS Factor-Based Subscales: Two Pairs of Scales Pair 1: Unrotated Two-Factor Solution Pair 2: Varimax-Rotated Two-Factor Solution The 16 BMIS Mood Adj. Pleasant-Unpleas. Arousal-Calm Positive-Tired Negative-Relaxed Positively- Worded Items Negatively- Worded Items Positively- Worded Items Negatively- Worded Items Positively- Worded Items Negatively- Worded Items Positively- Worded Items Negatively- Worded Items Lively x x x Happy x Sad x x x Tired x x x Caring x x x Content x Gloomy x x x Jittery x x x Drowsy x x Grouchy x Peppy x x x Nervous x x x Calm x x x Loving x x x Fed up x x x Active x x x Totals PW Items (^8 10 5 ) NW items (^8 2 2 ) Scale Total 16 12 7 6
Part 2. Four Ways to Implement the BMIS
Overview and Issues Over time, researchers have employed the BMIS with two different response scales, and used two different ways of scoring the BMIS test, resulting in four possible ways the test could be implemented and analyzed. The alternative response scales involved either following each mood adjective with the original 4-point Meddis response scale, or using a modification of the Meddis response scale that employed a 7-point rather than 4-point approach. (The original Mayer & Gaschke (1988) article used the 4- point scale but text of the article suggested that if greater test reliability were needed for a particular scale, a 7-point version of the Meddis scale could replace the 4-point scale. As a consequence, the scale has been used both ways). Subtractive versus Reverse Scoring. The BMIS is scored using both subtractive and reverse scoring. Although the original article containing the BMIS recommended subtractive scoring (Mayer & Gaschke, 1988), reverse scoring is now the recommended mode of scoring the test. Reverse Scoring. Reverse scoring refers to identifying items that measure the polar opposite of the dominant end of a scale (for example, “Unpleasant” Items on a Pleasant- Unpleasant Mood scale), and then reversing the scale values for those opposite items. In the case of the BMIS using a 4-point scale, it involves rescoring items such as “Sad” Key Advisory
Reverse scoring (recommended) correlates r = 1.
with subtractive scoring. To see how to convert
from one method to the other, please refer to the
later chapters of this manual.
(representing the “opposite” of the dominant Pleasant end of the scale) by reassigning a 4 as a 1, a 3 as a 2, a 2 as a 3, and a 1 as a 4 as indicated in Table 2.1. Table 2. Simple Example of Reverse Scoring a 4-point Likert Scale Response Definitely do not feel Definitely feel Original 1 2 4 4 Reversed 4 3 2 1 The same information is indicated for the 7-point version of the response scale in Table 2.2. Table 2. Simple Example of Reverse Scoring a 7-point Likert Scale Response Definitely do not feel Definitely feel Original 1 2 4 4 5 6 7 Reversed 7 6 5 4 3 2 1 In subtractive scoring, The conversions for both the 4-point response scales are transposed to the left columns of Table 2 .2. Subtractive Scoring. Subtractive scoring is common in situations in which both endorsements of the positively- and negatively-worded items on a scale constitute separate scores of interest. In such a case, as with pleasant and unpleasant mood, and with positive- and negative- self-esteem, sums of the positively- and negatively-worded items are summed separately and then the overall score is determined by taking the score of the positively-worded items and subtracting from it the score on the negatively-worded items (C.E. Noll & Bradburn, N. M., 1970; Schmitt & Allik, 2005).
Reverse scoring appears, in hindsight, to be a more elegant procedure than simple subtraction, but subtraction works as well. For that reason, we recommended reverse- scoring in online documents regarding the BMIS after the scale was published.
Part 3. Recommended Scoring: The Reverse-Scoring Method
Score the Pleasant-Unpleasant Scale Referring to Figure 1, score the Pleasant-Unpleasant scale using these steps:
- Convert the Meddis response scale (XX, X, V, VV) to numbers: XX = 1 X = 2 V = 3 VV = 4
- Next, reverse score the responses for: Drowsy, Fed up, Gloomy, Grouchy, Jittery, Nervous, Sad, and Tired. That is, recode, such that: XX = 4 X = V = 2 VV = 1
- Now, add up the scores for all 16 items to obtain the scale score. The sum is the total score on the Pleasant-Unpleasant scale. Score the Arousal-Calm Mood Scale
- Convert the Meddis response scale to numbers this way: XX = 1 X = 2 V = 3 VV = 4
- Next, add up the responses for:
- Next, reverse score the responses for: Calm, Tired. That is, recode, such that: XX = 4 X = V = 2 VV = 1
- Now, add up the scores for the following items (as is): Active, Caring, Fed up, Gloomy, Jittery, Lively, Loving, Nervous, Peppy, and Sad; (reverse-scored) Calm and Tired. The total represents the Arousal-Calm scale score. Scoring the BMIS for Positive-Tired Mood
- Convert the Meddis response scale to numbers this way: XX = 1
Part 4. Calculating the Range of 4-Point and 7-Point Scales that Use
Reverse and Subtractive Scoring
Worded (PW) and Negatively-Worded (NW) Items Many tests such as the BMIS make use of both “as is” or positively-worded (PW) items and reverse-scored or negatively-worded (NW) items. Each BMIS scale contains a different number of items we can designate as K items. Positively-worded items are those that are scored without alteration. For example, on the Pleasant-Unpleasant scale of the BMIS, a person’s endorsement of the adjective “Happy,” on the 4-point Meddis response scale can be added into the total test score as is, because happier people will be more inclined to endorse 3 or 4 on the measure, and that will directly add to their overall pleasantness score. People who endorse “Sad,” on the other hand, need to have their score reversed, because their 4 (for example) represents a lack of pleasant affect, and so the response is reversed to represent a “1” response. To generalize these ideas, and to treat them more formally, we can characterize a response scale made up of multiple items using the terms indicated in Table 4 .1. Table 4. Key Symbols and Terms K items The overall number of items on a scale PW items The number of “as is” (i.e., positively-worded) items, and NW items The number of negatively-worded (i.e., opposite-worded) items MinRsp The minimum response value for an item (e.g., 1 on the 4-point scale) MaxRsp The maximum response value for an item (e.g., 4 on the 4-point scale) TSmin The minimum value for a test scale TSmax The maximum value for a test scale Placeholder text between table and narrative
Calculating the Range of Scores for Reverse Scoring of the 4-Point Scale Under conditions of reverse scoring (and after reversing the negatively-worded items), the minimum and maximum scores on the BMIS, using the 4-point scale, can be easily estimated using the following two equations: Equations 4 .1 and 4. The Minimum and Maximum Values of a Reverse-Scored Scale TSmin = K x MinRsp (Equation 4.1) TSmax = K x MaxRsp (Equation 4.2) where: K : The overall number of items on a scale MinRsp: The minimum response value for an item (e.g., 1 on the 4-point scale) MaxRsp: The maximum response value for an item (e.g., 4 on the 4-point scale) TSmin: The minimum value for a test scale TSmax: The maximum value for a test scale Table 4 .2 provides the ranges for the four BMIS scales using a 4-point response scale. The left-most columns of the table indicates the scale names, and the minimum and maximum response possible for each item on the scales (always 1 for the minimum and 4 for the maximum). Equations 4 .1 and 4 .2 can then be used to calculate the minimum and maximum score for each of the test’s four scales. For the Positive-Tired scale, as an example, there are 7 items overall. The range is therefore from (7 x MinRsp) to (7 x MaxRsp) or from 7 x 1 to 7 x 4; that is, from 4 to 28. That, along with values for the remaining scales, are in the right-most columns of Table 4 .2.
Calculating the Range of Scores for Subtractive Scoring The case of the 4-point response scale The calculation of minimum and maximum values for substractive scoring are a bit different—and a bit more involved—although still fairly straightforward. This time, the two equations become as indicated in Equations 4.3 and 4.4. Equations 4. 3 and 4. 4. Equations for the Minimum and Maximum Values of a Subtractive-Scored Scale ( TSmin and TSmax) TSmin = (PW x MinRsp) – (NW x MaxRsp) (Equation 4.3) TSmax = (PW x MaxRsp) – (NW x MinRsp) (Equation 4/4) where: TSmin: The minimum value for a test scale TSmax: The maximum value for a test scale MinRsp: The minimum response value (e.g., 1 on a 4-point scale) MaxRsp: The maximum response value (e.g., 4 on the 4-point scale) PW items : The number of positively-worded (or “as is”) items, and NW items : The number of negatively-worded (or opposite-scored) items. Again using the Positive-Tired scale as an example, there are 7 items overall, PW=5 and NW=2. The minimum response is 1 and maximum is 4, yielding a minimum possible total on the scale of Minimum Value = (5 x 1) – (2 x 4) = 5-8 or - 3. The maximum value would be Maximum Value = (5 x 4) – (2 x 1) = 18. These values and those for the remaining scales are indicated in the right of Table 4.4.
It turns out that work in this area can be readily checked in the following way: Take the range of possible total scores (scale maximum – scale minimum value; that is, MaxRsp- MinRsp). Next, divide that by the total number of items on the scale, K. The results should be the range of the response scale minus 1 (i.e., 4 - 1, or 3 in this case). As you can see the computations in Table 4.4 all satisfy the check. The case of the 7 - point response scale Next, let’s examine the case of the 7-point scale. Table 4.5, right-hand side columns, contain the parallel computations for the 7-point scale. Once again, the check works out; that is, the Range of the Response Rating Scale = MaxRsp-MinRsp/K + 1 = 6
- 1, or 7, in each case. Table 4. 4 Ranges for BMIS Scales Using the Subtractive Method with 4-Point Response Alternatives Response Scale Number of Items on Scale Range of Values for Scoring Approach BMIS Scales Min rsp Max rsp Over- all (K) PW NW Intermediate Calculations Min. Valuea Max. Valueb Checkc PW x MinRsp NW x MaxRsp PW x MaxRsp NW x MinRsp Pleasant-Unpleasant 1 4 16 8 8 8 32 32 8 - 24 24 48/16= Arousal-Calm 1 4 12 10 2 10 8 40 2 2 38 36/12= Positive-Tired 1 4 7 5 2 5 8 20 2 - 3 18 21/7= Negative-Relaxed 1 4 6 5 1 5 4 20 1 1 19 18/6= Key Abbreviations: PW, positively-worded items (scored as is); NW, negatively-worded items (scored oppositely): MinRsp and MaxRsp, the minimum and maximum values on the Likert response scale; K, the total number of items on the scale a(PW x MinRsp) – (NW x MaxRsp) b(PW x MaxRsp) – (NW x MinRsp) cRange of the Response Rating Scale = [(MaxRsp-MinRsp)/K] + 1
Part 5. Translating Between 4- and 7-Point Scales When Item-Level Data is
Available
In situations where one has item-level information available, it is possible to convert from a 4 to a 7-point, or a 7 to a 4-point scale on a response-by-response basis. In this instance, each response is recoded so that it matches the range of the desired targeted scale. On the BMIS, the Meddis response scale 4- and 7-point scales can be compared to one another as indicated in Table 5.1. Table 5. 1 A Comparison of the 4- and 7-point BMIS scales definitely do not feel do not feel slightly feel definitely feel Scale Seen by Participants 4 - Point Scale XX X V VVV 7 - Point scale XXX XX X XV V VV VVV Scale as Scoreda 4 - Point Scale 1 2 3 4 7 - Point scale 1 2 3 4 5 6 7 aBefore any reversal for scoring Example. If a participant responded with a “2” (do not feel) to Sad on a 4-point scale, that would become a “3” (do not feel) after conversion to a 7-point scale. Going in the reverse direction, one could be to convert from a “2” on the 7-point scale to a “1.5”— i.e., midway between the 1 and 2 response, on the 4-point scale. Conversions from the 7- to the 4-Point Scale To convert from one scale to another, one can recode the individual item-level responses. To go from the 7- to the 4-point scale, for example, one could recode as
follows, where “MOODAdj” is a variable name that can stand in for any mood adjective on the BMIS (or any item on any other scale). These are indicated in Table 5. 2. Table 5. Examples of SPSS syntax for Converting the 4-Point BMIS Scale to 7 points and Back Again Software Help 5 .1 and 5 .2 A model for conversion of 4- to 7-point scales and back using the example of a recode statement in SPSS syntax To go from the 4 to the7-point scale, one would recode as follows: RECODE MOODadj (1=1) (2=1.5) (3=2) (4=2.5) (5=3) (6=3.5) (7=4) And to go from the 4 to the7-point scale, one would recode as follows: RECODE MOODadj (1=1) (2=3) (3=5) (4=7) Other treatments also exist, sometimes with a somewhat different focus and approach (Sanbandam, 2006) but the ones here are relatively complete by comparison to reports elsewhere (Colman, Norris, & Preston, 1997; IBM Support, 2016). Compatibility with the 2016 IBM Support Center Conception of Scale Translation The formulae here and their results can be compared against an alternative approach advocated by IBM support for SPSS statistical software (IBM Support, 2016). The anonymous expert recommends transforming Likert scales to a common scale that goes from zero to one. To do so, one can use Equation 5. 1.
