Measurement Properties of the Malay Version of the Golombok-Rust Inventory of Marital State (GRIMS) Among Urological Patients.

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1 ORIGINAL PAPER Measurement Properties of the Malay Version of the Golombok-Rust Inventory of Marital State (GRIMS) Among Urological Patients. Quek Kia Fatt, Low Wah Yun, And Hassan Razack, Loh Chit Sin, Chua ChongBeng To validate the Malay version of the Golombok-Rust Inventory of Marital State (GRIMS) among urological patients. The reliability and Internal consistency were assessed using the test-retest method and Cronbach's alpha. Sensitivity to change was assessed by mean differences and by the effect size. Internal consistency was excellent (Cronbach's alpha value 0.43 to 1.00). Test-retest correlation coefficient and Intraciass correlation coefficient were highly significant In majority Items (ICC=0.51 and above) while total scores of Mal-GRIMS exhibited high sensitivity and specificity. The Malay version of GRIMS Is suitable, reliable, valid and sensitive to clinical change In assessing the marital satisfaction in a Malaysian population. Key words: Malay version Golombok-Rust Inventory of Marital State, Cronbach's alpha, intraclass correlation coefficient, Internal consistency, test-retest reliability and validity. Malaysian Journal of Psychiatry March 2001, Vol. 9, No. 1 Introduction Lower urinary tract symptoms (LUTS) from symptomatic benign prostatic hyperplasia (BPH) characterized by suggestive of benign prostatic obstruction (BPO) is a common condition among elderly men (1). It is well known that LUTS often contribute to a higher degree of bother or bothersomeness to those who suffer severe symptoms. The symptoms of LUTS such as incomplete emptying, frequency, nocturia, urgency, urge incontinence and terminal dribbling has a great impact on the quality of life of the patients by interfering with their daily living and activities. The aspects which were reported to be mostly affected were sleep, leisure pursuits, social and family activities,psycho logical disturbances and relationship with partner (1). LUTS and quality of life (QOL) are considered to be inter related and an important aspect in the management of quality of life among elderly men. LUTS has not only affected the domains of quality oflife as mentioned earlier but also the marital or Low With Yun, Health Research Development Unit. Fatally of Medicine, University of Malaya, Kuala Lumpur. satisfaction with the partner. Marital satisfaction is one of the important components in the assessment ofone's quality of life. LUTS or BPH often contribute to an increase of anxiety, depression, psychiatric morbidity and dissatisfaction (2). These psychological disturbances have a great impact on their marital dissatisfaction. The effects of medical and surgical treatment can either improve their marital satisfaction or remain the same (3). The Golombok-Rust Inventory of Marital State (GRIMS) has become the most commonly used instrument in multicentre and international clinical trials to assess marital satisfaction. The GRIMS is an easy and fast instrument to be administered in identifying the severity ofmarital problems, partners perceives a problem in their relationship and fast or lack improvement either or both partners inaperiod of time (4). The existing measurement ofmarital satisfaction such as the GRIMS has been widely used in other countries and since culture and sociodemographic 23

2 QUEK KIA FATT et a/ differs from one country to another, the English version of the GRIMS needed to be translated and validated in order to be used in our population. The present study was conducted at University Malaya Medical Centre Kuala Lumpur and was designed to assess the reliability and validity of the Malay version of the Golombok-Rust Inventory of Marital State '(Mal-GRIMS) among urological patients. Patients and Methods All patients were assessed by using the Malay version of the Golombok-Rust Inventory of Marital State (Mal-GRIMS) (4). The 28-item Mal-GRIMS is able to assess the efficacy of different forms of therapy, investigate the impact of social, psychological, medical or other factors that has an effect on partners relationship. The Mal-GRIMS items cover the domains of satisfaction, communication, shared interest, trust and respect. Each ofthe 28 items on the Mal-GRIMS is assessed on a four-point scale, from 'strongly disagree' to `strongly agree'. The Mal-GRIMS has 14 reversed items and 14 are scored directly. The reversed items of the Mal-GRIMS are 3, 6, 7, 8, 11, 13,16,18,19, 21, 23, 24, 26 and 28. The higher the score, the more severe the relationship problem and vice-versa. The scores of 16 or less (undefined), 17 to 21 (very good), 22. to 25 (good), 26 to 29 (above average), 30 to 33 (average), 34 to 37 (poor), 38 to 41 (bad), 42 to 46 (severe problems) and 47 or more (very severe problems) (4). Inclusion and exclusion criterias were used to select patients for this study. For patients with LUTS, the inclus i on criteri as were that patients must be stable and Malay literate (understand and able to answer), whereas the exclusion criterias were patients who has been treated with surgical and medical treatment for lower urinary tract symptoms prior to this study, patients less than 40 years old, those who were unable to read, write or understand Malay, and patients with any chronic and acute diseases. As for the control group, the inclusion criterias include stable patients who were free from all major chronic and acute diseases while the exclusion criterias were those treated with BPH and UTI except for patients who were treated for renal stone with no or mild symptoms. The study protocol was approved by the Ethics Committee ofuniversity Malaya Medical Centre, Kuala Lumpur. Study sample The Malay version of GRIMS was assessed in two different samples. Validity and reliability were Studied in agroup ofpatients admitted fortransurethral resection ofthe prostate (TURP)(N= 18) and control subjects (N=19). Management decisions and diagnosis were entirely done by the Urologist (A.H.R) in all casesbased on clinical criteria such asmedical history, physical and rectal examinations. Data Collection All patients who were selected in the study gave their written informed consent to participate in the study after being explained of the nature of the study prior to the commencement ofthe study. After agreeing to participate, the patients were given the Mal-GRIMS form to be completed. The Mal-GRIMS. was selfadministered although assistance was available by one ofthe authors (K.F.Q) of this study to assist the patients where necessary. All patients who were involved in this study were retested at twelve weeks after the first administration of the Mal-GRIMS (baseline). Similarly in orderto assess the sensitivity to change of the marital satisfaction, patients who completed the questionnaires 1 week before the surgical treatment were retested at three months after TURF. Data Analysis The Cronbach's alpha coefficientwas used to assess the internal consistency ofthe Mal-GRIMS (5). The internal consistency is the value ofcronbach's alpha for the scale when an individual item is excluded from the analysis. The intraclass correlation coefficient (ICC) which is derived from analysis of variance (ANOVA) repeated measures model was used to assess the test-retest reliability (ICC). The value of ICC 1.0 indicating perfectly reliable while b indicting totally unreliable (6). The effect size was used to assess the sensitivity to change by dividing the mean difference between Mal-GRIMS before and after 24

3 MEASUREMENT PROPERTIES OF THE MALAY VERSION OF THE GOLOMBOK-RUST INVENTORY OF MARITAL STATE (GRIMS) AMONG UROLOGICAL PATIENTS TURP with the standard deviation of the scores before TURP (7). The Guyatt statistic was employed in this study and was analyzed by dividing the mean differences of Mal-GRIMS scores before and after TURP with the standard deviation of stable patients (control patients) (8). The sensitivity of the Mal-GRIMS was assessed by comparing between the mean of pre-treatment and post-treatment item scores of patients who has undergone TURP whereas specificity was assessed by comparing the pre-treatment and post-treatment items scores in control patients. Results A total of 37 respondents took part in the Malay version of the GIUMS validity and reliability study. Patients with LUTS had higher Mal-GRIMS scores indicating severe marital dissatisfaction. Of the 37, 19 patients has total mean scores of Mal-GRIMS 26.$5(=6.64)while 18 patientsundergoingturp has total mean scores of Mal-GRIMS ( = 7.55) respectively. There was high internal consistency for majority items of the Mal-GRIMS indicating *a high level of homogeneity among items in the scale. The testretest reliability which was assessed in 19 patients after 12 weeks interval indicated total scores ofmal- GRIMS with an ICC of 0.90 (p<0.001) (Table 1). Table 1:Vaildity and Reliability: Test-Retest score, intraclass correlation coefficient and Internal consistency for individual GRIMS items (control group) GRNS Items Intraclass Correlation Coefficient (ICC) Test Score Retest Score Man Difference 96% Confidence Interval Loww Upper Total pe0.001 (oral ICCs(r) pco.01 foralpearson'scoa6iclant(') Crorbadi'sayhaawtsMalCmrbach'satphavaluaywnforeach Item rspresenttheetfectotremovintwntsm fromfromthecaculationoftheaphawlue (sya Item 1 Isomkted.t a resukmgvalueforthesalo IsO.67, If ftem2lsantted. It is 0.97, andsofom)( t ts for paked comparisons signikant ("')

4 QUEK KIA FAIT ei of Table 2: Sensitivity to change : mean scores before and after TURP, effect size and Guyatt Statistic GRIME items PreTURP PostTURP Differences Effect size Guyatt statistic all Total Effect size= difference/ PreTURP Guyatt statistics=mears difference/ of stable patients (control group) t test for paired comparisons not significant Table 2 shows pre and post scores, mean difference, effect size, and the Guyatt statistic for individual items and total scores ofthe Mal-GRIMS. The mean pre-intervention score on the total Mal-GRIMS was ( = 7.55) while the mean post-intervention score was ( = 6.77). Although the urinary symptom s improvement was seen in these patients nevertheless the marital state was found to be relatively unchanged. Majority ofthe items ofthe Mal-GRIMS indicated less sensitivity and specificity to the effects of treatment (Table 3). Significant changes were only observed in items 2, 4 and total scores in the LUTS group. The lowest magnitude ofchange was noted in items 4, 11, 18 and 27. Similarly, majority items in the control group did not approach significant levels except for item 15. However, high sensitivity and specificity was observed in the total scores where significant changes were observed in the surgical group compared to the control group where the total scores was not significant (Table 3). Table 4 shows the discriminant validity of the Mal-GRIMS where significant differences were observed in some items and the total scores. Table 3: GRIMS Items characteristics of patients undergoing TURP and the control group: Sensitivity and Specificity Sensitivity N Changes SEM t statistics p value all ' Total

5 MEASUREMENT PROPERTIES OF THE MALAY VERSION OF THE GOLOMBOK-RUST INVENTORY OF MARITAL STATE (GRIMS) AMONG UROLOGICAL PATIENTS Table 4: GRIMS items characteristics: Discriminant validity GRIMS Items PreTURPpatents SEM Control SEM Differences SEM 95% Confidence Interval Lower Higher pvaiue E Total Discussion The Mal-GRIMS is a valid, sensitive and reliable instrument in detecting marital dissatisfaction in patients with LUTS. Its ability to discriminate between patients with LUTS and control shows a relatively high level of sensitivity and specificity although majority of the items did not indicate significant differences. The high effect size obtained in some items when the questionnaire was administered before and after treatment (TURF) indicates a high degree of sensitivity to change. The discriminant validity shows Mal-GRIMS is able to discriminate between the surgical group and control. The test-retest exhibits no statistical significant in all items of Mal-GRIMS where minimal changes of marital satisfaction occurred at three months. Therefore, the Mal-GRIMS is reliable and valid. The reasons for the test-retest to be carried out at twelve weeks interval was because most of the patients in the surgical group only achieved maximum benefits or improvement ofsymptoms at 8 weeks to 12 weeks and so then it was easier to make comparison between the patients with LUTS in the surgical and control groups. The reasons why the majority of its items exhibited less changes or improvements in marital satisfaction in the surgical group compared to the control group following treatmentarepossibly dueto theunchanged sustained and stagnant lifestyle being maintained among most elderly men with their partners. These findings show that scores obtained using the Mal-GRIMS are reliable and can be used in assessing the marital satisfaction in patients with LUTS or other medical disorders. The Mal-GRIMS score obtained from this study is validated in a Malaysian population and is consistent with scores of Mal-GRIMS validated in various countries (4). 27

6 QUEK KIA FATT a at The performance measurement properties of the Mal-GRIMS validated in this Malaysian population and Mal-GRIMS validated in other countries show that the Mal-GRIMS approaches to that of the English version of GRIMS (4). Conclusion The reliability and validity ofthemal-grims for37 patients were tested. The intraclass correlation coefficient (ICC) for the total scores of the Mal- GRIMS indicated high intraclass reliability. The high Cronbach's alpha coefficient indicated that Mal- GRIMS has good internal consistency and these findings indicate that the Mal-GRIMS is a useful and accurate tool for assessing the severity of marital state due to LUTS in a Malaysian population. Acknowledgement The authors would like to express their gratitude to the University Malaya's Research and Development Management Unit for providing the research grant for this study. References 1. Lukacs B. Management ofsymptomatic BPH in France: Who is Treated and How? European Urology, 1999: 36(3) : Quek KF, Low WY, Razack AH, Loh CS. Psychological Effects of Treatment for Lower Urinary Tract Symptoms. British Journal Urology International, 2000 : 86 : Thorpe AC, Cleary R, Coles J, Reynolds J, Vernon S, Neal S.E. Written Consent About Sexual Function in Men Undergoing Transurethral Prostatectomy. British Journal Urology, 1994: 74(4) : Rust I, Bennum I, Crowe M, Golombok S. The Golombok-Rust Inventory of Marital State. NFER-NELSON, Oxford Cronbach U. Coefficient Alpha and the Internal Structure oftest. Psychometrika,1951:16: DeyoRA,Dichr P, Patrick DL. Reproducibility and Responsiveness ofhealth Status Measures. ControlClinicalTrials,1991: 12(1):142S-158S. 7. Cohen J. Statistical Power Analysis for the Behavioral Sciences. New York: Academic Press. 1977: Guyatt G, Walter S, Norman G. Measuring Changes Overtime: Assessing the Usefulness of Evaluative Instruments. Journal Chronic Disease, 1987:40: