Lab Report: The Multi-Dimensional Perfectionism Scale (MDPS)

Lab Report: The Multi-Dimensional Perfectionism Scale (MDPS)

Instructions

The aim of this practical exercise is to introduce you to a psychological questionnaire that has been used in research on perfectionism, a personality variable, and to further develop your statistical and psychometric skills using Jamovi. A number of key references are available on Canvas.

This lab report will comprise 40% of your final grade for this paper. It should be submitted through TURNITIN. Please check your similarity report on TURNITIN before submitting.

After completion of this assignment, you will:

1. Be able to describe the Multidimensional Perfectionism Scale (MDPS) including its purpose, administration, scoring and some important psychometric properties.

2. Be able to do simple and more advanced psychometric analyses of questionnaire data using Jamovi including – descriptive statistics, Cronbach’s alpha, McDonald’s omega, item-rest correlations, test-retest reliability, and exploratory factor analysis.

DATASET

In this practical exercise, you will use two Jamovi datasets that you can download from Canvas labelled: PSYC603_2026_File1_MDPS.csv and PSYC603_2026_File2_MDPS.csv

• PSYC603_2026_File1_MDPS: This dataset contains the class responses on the MDPS from one single occasion in Week 1 of Semester 1 or early in Week 2. However, it also contains data from previous PSYC603 classes. The extra data are added so that we have a large enough sample (n=1232) to do factor analysis. In fact, you will be dealing with n + 2 participants because you will be adding responses from one more participant in the lab class - yourself – and dummy data to create your own unique dataset. This means we expect all your lab report results to be slightly different from any of your classmates.

• PSYC603_2026_File2_MDPS: This smaller dataset comprises the responses of a smaller number of students who completed the MDPS on two separate occasions in the lectures of Week 1 and Week 2. You will only use this second file to calculate the test-retest reliability of the MDPS.

LAB REPORT ASSIGNMENT FORMATTING INSTRUCTIONS:

• Your lab report must have a title page that includes - name, student ID, course name and code, title of lab report, date report is due, lab stream you are in, and your lab tutor’s name.

• Use Times New Roman (font size 12) or Arial (font size 11), with 1.5 line spacing.

• Marks will be taken off for untidy presentation, poor grammar, spelling errors, and insufficiently following the assignment instructions.

• There is no specific word limit as such, however, your lab report (not including the title page) should be no more than six (6) sides of A4 text. You should include the table showing the results of your factor analysis as an appendix. So, you need: (i) a title page, (ii)  6 pages of text to answer Q1– Q12 listed below,  (iii) a 1-page appendix with the table of factor analysis results for Q.10 and, (iv) a reference list.

• You do not have to repeat the 12 questions in your lab report. Just writing Q.1., Q.2.  etc. will do.

LAB REPORT ASSIGNMENT INSTRUCTIONS:

Present work at appropriate academic standard: This will be marked globally throughout the assignment. You will be required to demonstrate academic clarity and presentation – this involves providing clear and concise arguments and correct APA 7th formatting, good grammar, clear writing, and correct spelling (e.g., referencing, graphs, figures and graph/figure headings). (3 marks)

Answer each of the following questions (total/42):

• Use dataset PSYC603_2026_File1_MDPS to answer all the questions except for Q.7.

• Use PSYC603_2026_File2_MDPS to answer Q.6 and Q.7

Q.1.

• Describe in your own words what you understand perfectionism is.

• Describe an incident from your own experience when perfectionism has been a useful/positive/adaptive trait for you or someone you know (or a character in a book, TV series, or movie).

• Describe another incident from your own experience where perfectionism has been a negative/maladaptive/disadvantageous trait for you or someone you know (or a character in a book, TV series, or movie). (4 marks)

Q.2. Using the Jamovi package, score your own MDPS and use your results to illustrate how it is scored (4 marks).

Hint: Think about how the total score and the subscales are calculated.

• You should report your total perfectionism score and each of your six subscale scores as well.

• Interpret your own total perfectionism score with reference to the class norms i.e. mean and SD (see Q.3 below).

Note: To keep your real answers private, you can select any of the 3 sets of scores you have entered into the dataset.

Q.3. Calculate the following for the total MDPS score using the full sample:

• Mean, median, mode, and range.

• Standard deviation

• Kurtosis and skewness

• Present a histogram of the distribution of total scores for the dataset using correct APA formatting for the figure title. (3 marks)

Q.4. Does the mean total MDPS score differ for males and females in the class? Use a t-test to see if there is a significant difference. (2 marks)

Q.5. Is there a significant correlation between age and perfectionism? How do you interpret this correlation? (2 marks)

Q.6.

• Calculate Cronbach’s alpha and McDonald’s omega for the full 35 item scale using the larger sample (File 1).

• Then calculate Cronbach’s alpha and McDonald’s omega for the smaller test-retest sample (File 2) twice - first for Time 1 and then for Time 2.

• Comment on the internal consistency (i.e., reliability) of the MPDS for both files. (3 marks)

Q.7. What is the test-retest reliability of the total MDPS score at an approximate 7-day interval? Is this acceptable reliability? (2 marks)

Hint: use file- PSYC603_2026_File2_MDPS for this question.

Q.8. Look at your item-rest correlations for all the 35 items. Comment on which items have the lowest and highest correlations. Which items, if any, would you remove to shorten this quite long questionnaire and why?  (4 marks)

Q.9. Explain which item is the easiest item, and which is the most difficult item – present a mean and SD for each. Looking at the wording of these items, reflect why these might be the most difficult/easiest items.  (3 marks)

Q.10. Examine a six-factor structure of the MDPS using principal components analysis and Varimax rotation. (6 marks)

• Include a table showing rotated factor loadings of the MDPS items on each of the 6 factors. Use the handout on presentation of factor analysis results to guide you (see Canvas >> assignments >> FA_Table_Guidelines.pdf).

• Label your six components/factors and calculate Cronbach’s alpha for each factor and report your values in the table.

• Compare your six-factor solution with the subscales claimed by Frost to underpin the MDPS and comment. Briefly comment on what other researchers have reported on the factor structure of the MDPS.

• Use the last page on Lab Handout 2 to help guide your discussion.

Q.11. Calculate the item-rest correlations for each of the subscales. What are you noticing about the scores for the items with the lowest and highest correlations in Q8? (2 marks)

Q.12. (4 marks)

What are the analyses that you have completed telling you about perfectionism as a psychological construct?

Does knowing your subscales scores in addition to your total score provide you with any additional insights about yourself? Was there anything that surprised you or confirmed what you have been perceiving about yourself?