The development of a questionnaire to measure the severity of symptoms and the quality of life before and after surgery for stress incontinence

BJOG: an International Journal of Obstetrics and Gynaecology November 2003, Vol. 110, pp. 983 988 The development of a questionnaire to measure the severity of symptoms and the quality of life before and after surgery for stress incontinence Sigurd Kulseng-Hanssen a, *, Ellen Borstad b Objectives To develop and validate a short questionnaire recording the severity of symptoms and the quality of life, pre- and post-operatively, in women undergoing surgery for stress incontinence. Design The questionnaire was designed from previously designed questionnaires and pilot studies. In this study, it was tested for validity and reliability using standard psychometric techniques. Data from the questionnaire are reported to a national database, which generates reports for comparison of surgical procedures, departments and surgeons. Setting Tertiary referral urogynaecology units at Bærum and Aker Hospitals, Norway, and 22 Norwegian departments of gynaecology. Population Fifty and 65 women with stress incontinence from Bærum and Aker hospitals, respectively, and 628 women with stress incontinence from 22 Norwegian departments of gynaecology. Methods Stress Incontinence, Urge Incontinence and Quality of Life Indices were constructed. Internal consistency of the indices was measured by Cronbach s alpha and test retest reliability by Bland Altman plots. Stress Incontinence Index was tested against stress test and Urge Incontinence Index and Stress Incontinence Index were tested against the 24-hour pad test. Quality of Life Index was tested against a part of the King s College Hospital Quality of Life Questionnaire. Main outcome measures Face and content validity. Missing values of the questionnaire. Reliability and internal consistency. Criterion validity. Results The 628 women completed a mean of 98.2% of all the questions. The content validity was good. The reliability was good in terms of test retest reliability and internal consistency. The criterion validity of stress and urge incontinence was tested against the stress and 24-hour pad tests. The correlation between the indices and the objective tests was moderate. The correlation between the Quality of Life Index and the physical and social part of the previously validated King s College Hospital questionnaire was good. Conclusions The questionnaire is easy to understand and complete and is a valid and reliable instrument for assessment of the symptoms of incontinence and the quality of life. Pre- and post-operative evaluation of women with stress incontinence was performed in a standardised setting in 22 of the 37 Norwegian departments and the reporting to a national database was successful. Comparison of surgical procedures, departments and surgeons is possible. INTRODUCTION In 1996, 31 of the 37 departments of obstetrics and gynaecology in Norway that performed surgery for urinary incontinence completed a questionnaire concerning follow up after such surgery. Only 16% of the departments had evaluated the outcome of their incontinence surgery 1. Most departments stated lack of time as the main reason for not a Department of Obstetrics and Gynaecology, Bærum Hospital, Norway b Department of Obstetrics and Gynaecology, Ullevål Hospital, Oslo, Norway * Correspondence: Dr S. Kulseng-Hanssen, Bærum Hospital, Box 83, 1309 Rud, Norway. D RCOG 2003 BJOG: an International Journal of Obstetrics and Gynaecology PII: S 1 47 0-0 3 2 8(0 3)0 1 9 06-2 having assessed their results. They were, however, willing to give priority to follow up if they were offered a simple follow up procedure that was not time consuming. A committee of five urogynaecologists, two of whom had been appointed by the Norwegian Association of Gynaecology and Obstetrics, was set up and all departments were invited to a meeting to discuss how to design a national follow up procedure. There was agreement that a symptom-specific questionnaire and recording of simple objective outcome measurements would be acceptable. The questionnaire should not exceed two A4 pages. Existing psychometrically tested disease-specific questionnaires were evaluated. None was found to meet all the requirements set by the committee. The questionnaires of Jackson et al. 2 and Kelleher et al. 3 were found to be too extensive for our purpose. Uebersax et al. 4 found that a short form version of their incontinence impact questionnaire and urogenital distress www.bjog-elsevier.com

984 S. KULSENG-HANSSEN & E. BORSTAD inventory was as useful as their long form version 5. Black et al. have developed a short form questionnaire 6 for use in women with stress incontinence. The questionnaire did not however, deal with urge incontinence. Because 81% of our women undergoing incontinence surgery have mixed incontinence 7, we wanted a questionnaire that also recorded the degree and impact of urge incontinence. Our previous experience 8 using the questionnaire of Jackson et al. 2 was used to develop a short questionnaire based on the questionnaire created by Black et al. 6. The aim of this study was to design and validate a short questionnaire to assess the severity of symptoms and the quality of life in women with stress incontinence and mixed incontinence before and after surgical treatment. The Stress and Urge Incontinence and Quality of Life Questionnaire was designed with the purpose of being acceptable to all gynaecological departments performing incontinence surgery in our country. METHODS Fig. 1. Pre-operative Stress Incontinence Index (n ¼ 581, median ¼ 9). Fig. 2. Pre-operative Urge Incontinence Index (n ¼ 610, median ¼ 4). The questionnaire consists of symptoms and quality of life sections. Two indices are constructed from the symptom section. The Stress Incontinence Index is made up of three items. One item is a composite of nine questions on activities that cause leakage (when the woman coughs, sneezes, laughs, walks up or down stairs, rises from the bed, lifts heavy objects and during physical activity, sports and intercourse). The second and third items ascertain to how often stress incontinence is experienced (never, 1 4 times a month, 1 6 times a week, once a day and more than once daily) and the amount of leakage (nothing, drops/moist underwear, dripping/wet underwear, running/passes through all clothes, and running down the legs or down to the floor). The Urge Incontinence Index is composed of two questions about how often and to what extent urge incontinence is experienced. The items concerning urge incontinence were constructed in the same way as the Stress Incontinence Index. One question, not included in the indices, asks the woman to decide which bothers her more, urge or stress incontinence, or do they equally bother her. The Quality of Life Index is constructed of four items: (1) the number of incontinence diapers used (none, 1 3 per week, 4 6 per week, 1 4 per day and more than 4 per day), (2) how often activities are avoided due to fear of leakage (never, seldom, sometimes, often, always), (3) how often places or situations are avoided due to fear of leakage (never, seldom, sometimes, often, always) and (4) how leakage influences holidays, family life, social life and sleep during the night. These last four questions are marked yes, no or not relevant, which have scores 1, 0 and 0, respectively. Except the first stress incontinence item, therefore, all the items are expressed in a scale of five categories, with scores of 0 4. The nine questions from the first stress item has the possible choices yes, no and not relevant. Scores for these questions are 1, 0 and 0, respectively. The sum score from the nine stress incontinence questions are recalculated into five categories (0, 1 3, 4 5, 6 7 and 8 9) to give this item the same relative weight as the others. Three questions were not implemented in an index: the number of urinary infections treated the last six months (no, 1, 2 3, 4 and more than 4), how sexual life is influenced by the leakage before and after treatment (not relevant, become much better, become a little better, unchanged, become a little worse, become much worse) and treatment satisfaction (very satisfied, moderately satisfied, neither satisfied nor dissatisfied, moderately dissatisfied and very dissatisfied). The questionnaire was posted to each woman for completion at home. The questionnaire was approved by the Norwegian state data registry for use in a national database, provided the identification of each woman and each surgeon was given by a number code known only to the department where the operation was performed. The surgeon recorded objective outcome values, data about previous incontinence surgery, the identity of the surgeon, whether the incontinence procedure was combined with vaginal surgery and data about complications. Details about these items will be published in the following paper 7.

FEMALE URINARY INCONTINENCE QUESTIONNAIRE 985 Fig. 3. Pre-operative Quality of Life Index (n ¼ 576, median ¼ 9). The Teleform software was used to create the questionnaire forms, to read them using a scanner and to interpret them. After evaluation and correction when necessary by a secretary, the data were transferred by the Teleform software to a database. The questionnaire occupied two A4 pages. It should be completed before the operation and 6 12 months and three years after the operation. Completed questionnaires are posted from the departments to a national centre where the scanning is performed. A report comparing the information from individual departments with the mean results from all departments is generated twice every year. In a pilot study, the questionnaire was tested on 50 women for ease of understanding, ambiguity and redundancy. To assess the test retest reliability, the questionnaire was posted a second time to 65 women. Fifty-nine questionnaires were received. The Urge Incontinence Index was compared in all these women. Due to missing data, the Stress Incontinence and Quality of Life Indices were compared in 57 and 55 women, respectively. The interval Fig. 5. Bland Altman plot of the Stress Incontinence Index. A circle and a circle with a line through the centre represent one and two women, respectively. Number of radial lines from the centre of the circle represents the number of women having the same value. between the completions of the two questionnaires was 22 [SD 14] days. From September 1, 1998, till March 1, 2000, we received 628 pre-operative forms from 20 departments in Norway. Internal consistency of the indices was tested using Cronbach s alpha. Criterion validity was evaluated by comparing the Stress Incontinence Index with the stress test and Stress and Urge Incontinence Indices with the 24-hour pad test. The stress and 24-hour pad tests were performed in 581 and 495 of the women, respectively. The King s College Hospital Quality of Life Questionnaire was translated into Norwegian. The criterion validity of our own Quality of Life Index was evaluated by comparing it with an index made from physical and social limitations and the use of pads in the King s College Hospital Quality of Life Questionnaire, an established and previously validated measure of quality of life. Fifty-two women completed both the Stress and Urge Incontinence and Quality of Life Questionnaire and the physical and social limitations questions of the King s College Hospital questionnaire. Fig. 4. Number of women reporting leakage during different activities (n ¼ 582). Fig. 6. Bland Altman plot of the Urge Incontinence Index.

986 S. KULSENG-HANSSEN & E. BORSTAD The statistical methods used were Bland Altman plot, Cronbach s alpha, Spearman s rank correlation, and the Wilcoxon s signed rank test. RESULTS Fig. 7. Bland Altman plot of the Quality of Life Index. The Stress Incontinence Index (Fig. 1) was positively skewed with a median of 9 and a range of 0 12. The Urge Incontinence (Fig. 2) and Quality of Life Indices (Fig. 3) had medians and ranges of 4 (0 8) and 8 (0 16), respectively. One hundred and fourteen women (19%) reported stress incontinence and no urge incontinence (Urge Incontinence Index ¼ 0) (Fig. 2). In Fig. 4, the number of women that report leakage during different activities is depicted. Nearly all women leak when they cough and sneeze, but less than half of the women leak when they get out of bed. During the pilot study, several changes were made to the content and wording of the questions to improve face and content validity. Only a few data were missing from the 628 questionnaires. Of the nine questions concerning the symptoms of stress incontinence, data were missing in 0 2.4% of the questionnaires. Data were missing in 0.2% and Fig. 9. Scatter plot of the Stress Incontinence Index and the 24-hour pad test (Rho ¼ 0.3, P ¼ 0.01). 0.6%, respectively, in the items reporting how often and the severity of stress incontinence. In the Urge Incontinence Index, the two items had missing data in 0.3% and 2.9%, respectively. In the four items of the Quality of Life Index, data were missing in 0.5%, 1.4%, 2.6% and (2.9%, 3.7%, 2.9%, 4.1% for the last item), respectively. Data about number of urinary tract infection per year were missing in 1.3% of the questionnaires. Data whether sexual life was influenced by the leakage were missing in 4.8%. Thirtyfive percent of the women were not sexually active. A mean of 1.8% of all the questions was not completed. We measured the test retest reliability of the questionnaire by Bland Altman plots and internal consistency by Cronbach s alpha. Bland Altman plots of the difference between first and second recording against the mean of the two recordings of all the indices are given in Figs 5 7. The mean of the differences between the first and the second recordings was positive in the Urge Incontinence and Quality of Life Indices (0.25 and 0.05, respectively) and negative ( 0.5) in the Stress Incontinence Index, but these means were not statistically significantly different from zero. The Cronbach s alpha of the Stress Incontinence, Urge Incontinence and Quality of Life Indices were 0.75, Fig. 8. Scatter plot of the Stress Incontinence Index and the standardised stress test (Rho ¼ 0.3, P ¼ 0.01). Fig. 10. Scatter plot of the Urge Incontinence Index and the 24-hour pad test (Rho ¼ 0.23, P ¼ 0.01).

FEMALE URINARY INCONTINENCE QUESTIONNAIRE 987 Fig. 11. Scatter plot of an index constructed of King s College Hospital physical and social limitations and number of pads used and the Quality of Life Index (Rho ¼ 0.77, P ¼ 0.01). 0.77 and 0.72, respectively. The Cronbach s alpha of the first item of the Stress Incontinence Index was 0.71. Removing any of the nine questions in this item decreased the Cronbach s alpha. All nine questions are therefore used. The question how many times have you been treated for urinary tract infection during the last year? reduced the internal consistency of the Quality of Life Index and was therefore omitted from the index. Criterion validity tests the index against factors known to be related to the condition under investigation. Stress Incontinence Index tested against the stress test (Fig. 8) and Urge Incontinence Index (Fig. 9) and Stress Incontinence Index (Fig. 10) tested against the 24-hour pad test revealed Spearman s correlation coefficients of 0.31, 0.23 and 0.30, respectively ( P ¼ 0.01 for all correlations). The Quality of Life Index tested against an index made from the physical and social limitations in the King s College Hospital Quality of Life Questionnaire (Fig. 11) revealed a correlation coefficient of 0.77 ( P ¼ 0.01). DISCUSSION The questionnaire is easy to understand and to complete. A mean of 98.2% of all the questions was completed. The questionnaire is supposed to be completed without assistance; however, because this questionnaire, like other questionnaires 2,3,6, has some missing answers, we recommend that the doctor or nurse discusses the questionnaire with the women to obtain a complete response. The test retest reliability of the questionnaire is good. The Bland Altman plots show that the women scored slightly higher during the first recording. The means of the differences are clinically acceptable and these means were not statistically significantly different from zero. The internal consistency is acceptable with the values of Cronbach s alpha being more than 0.7. Criterion validity tests the index against factors known to be related to the severity of incontinence. No objective factors are known to be strongly associated with the symptoms of incontinence. An index constructed of questions about when, how often and how much a woman leaks urine during stress could be expected to be associated with standardised stress and 24-hour pad tests, especially if the patient, during the 24-hour pad test, sought situations causing leakage. There was a moderate correlation between the Stress Incontinence Index and the stress and 24-hour pad tests, but as can be seen from Figs 8 and 9, a large group of women reported severe stress incontinence while they are not leaking or leaked a small amount during the stress and 24-hour pad tests. This is, however, in accordance with clinical experience. Many women complaining of stress incontinence do not leak during a stress test; however, if they jump or run for a longer period, they do leak 8. Although the written information asked the women to seek situations causing leakage during the 24-hour pad test, many women performed the test on a quiet Sunday, because they were too busy on weekdays. There was a moderate correlation between the Urge Incontinence Index and 24-hour pad test, but as can be seen from Fig. 10, many women reported severe urge incontinence while they are not leaking at all or leaking only a small amount during 24-hour pad test. Sandvik et al. 9 quoted a higher correlation (R ¼ 0.48, P < 0.001) between the 24-hour pad test and a severity index constructed of frequency of leakage and amount of leakage of urine. Their women were enrolled from the general population with less severe incontinence than the women in our study. The criterion validity of the Quality of Life Index was confirmed against the physical and social parts of the previously validated King s College Hospital questionnaire 3. Black et al. 6 did not include questions about urge incontinence in their questionnaire and were therefore unable to evaluate the effect of a surgical procedure on urge incontinence. In one of their studies, 76% of the women undergoing surgery for stress incontinence reported symptoms of urge incontinence 10. In our study using the Stress and Urge Incontinence and Quality of Life Questionnaire in women undergoing surgery for stress incontinence, 81% reported urge incontinence 7. Some women may be cured of urge incontinence after surgery for stress incontinence, but others may experience urge incontinence for the first time after their operation. The questionnaire is comprehensive enough to be accepted and applied by busy clinicians. The reporting of the results of this questionnaire to a national database has been successful. Pre- and post-operative evaluation of women with stress and mixed incontinence by this questionnaire is now performed in a standardised setting in 30 of the 37 gynaecological departments in Norway. The half-yearly reports yield information on the quality of treatment and the standardised recording makes the performing of clinical studies with an adequate number of women much easier. The clinical use of the Stress and Urge Incontinence and

988 S. KULSENG-HANSSEN & E. BORSTAD Quality of Life Questionnaire is reported in the accompanying paper 7. References 1. Lose G, Kulseng-Hanssen S, Nilsson CG. Aspects on the actual practice of surgical management of urinary incontinence in Norway and Finland. Acta Obstet Gynecol Scand Suppl 1998;168:25 28. 2. Jackson S, Donovan J, Brookes S, Eckford S, Swithinbank L, Abrams P. The Bristol Female Lower Urinary Tract Symptoms Questionnaire: development and psychometric testing. Br J Urol 1996; 77(6):805 812. 3. Kelleher CJ, Cardozo LD, Khullar V, Salvatore S. A new questionnaire to assess the quality of life of urinary incontinent women. Br J Obstet Gynaecol 1997;104(12):1374 1379. 4. Uebersax JS, Wyman JF, Shumaker SA, McClish DK, Fantl JA. Short forms to assess life quality and symptom distress for urinary incontinence in women: the Incontinence Impact Questionnaire and the Urogenital Distress Inventory. Continence Program for Women Research Group. Neurourol Urodyn 1995;14(2):131 139. 5. Shumaker SA, Wyman JF, Uebersax JS, McClish D, Fantl JA. Health-related quality of life measures for women with urinary incontinence: the Incontinence Impact Questionnaire and the Urogenital Distress Inventory. Continence Program in Women (CPW) Research Group. Qual Life Res 1994;3(5):291 306. 6. Black N, Griffiths J, Pope C. Development of a symptom severity index and a symptom impact index for stress incontinence in women. Neurourol Urodyn 1996;15(6):630 640. 7. Kulseng-Hanssen S. A national database for female urinary incontinence surgery. Br J Obstet Gynaecol 2003. In press. 8. Kulseng-Hanssen S. The clinical value of ambulatory urethral pressure recording in women. Scand J Urol Nephrol 2001;207(Suppl): 67 73. 9. Sandvik H, Hunskaar S, Seim A, Hermstad R, Vanvik A, Bratt H. Validation of a severity index in female urinary incontinence and its implementation in an epidemiological survey. J Epidemiol Commun Health 1993;47(6):497 499. 10. Black NA, Griffiths JM, Pope C, Stanley J, Bowling A, Abel PD. Sociodemographic and symptomatic characteristics of women undergoing stress incontinence surgery in the UK. Br J Urol 1996;78(6): 847 855. Accepted 25 April 2003