Validation of the Swedish short forms of the Pelvic Floor Impact Questionnaire (PFIQ-7), Pelvic Floor Distress Inventory (PFDI-20) and Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12)
2011; Informa; Volume: 90; Issue: 5 Linguagem: Inglês
10.1111/j.1600-0412.2011.01085.x
ISSN1600-0412
AutoresPia Teleman, Karin Stenzelius, Linda Iorizzo, Ulf Jakobsson,
Tópico(s)Urinary Tract Infections Management
ResumoActa Obstetricia et Gynecologica ScandinavicaVolume 90, Issue 5 p. 483-487 MAIN RESEARCH ARTICLEFree Access Validation of the Swedish short forms of the Pelvic Floor Impact Questionnaire (PFIQ-7), Pelvic Floor Distress Inventory (PFDI-20) and Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12) PIA TELEMAN, PIA TELEMAN Institute of Clinical Sciences, Lund University, Lund Department of Obstetrics and Gynecology, Skåne University Hospital, LundSearch for more papers by this authorKARIN STENZELIUS, KARIN STENZELIUS Department of Urology, Skåne University Hospital, MalmöSearch for more papers by this authorLINDA IORIZZO, LINDA IORIZZO Institute of Clinical Sciences, Lund University, Lund Department of Obstetrics and Gynecology, Skåne University Hospital, LundSearch for more papers by this authorULF JAKOBSSON, ULF JAKOBSSON Centre for Primary Health Care Research, Faculty of Medicine, Lund University, Lund, SwedenSearch for more papers by this author PIA TELEMAN, PIA TELEMAN Institute of Clinical Sciences, Lund University, Lund Department of Obstetrics and Gynecology, Skåne University Hospital, LundSearch for more papers by this authorKARIN STENZELIUS, KARIN STENZELIUS Department of Urology, Skåne University Hospital, MalmöSearch for more papers by this authorLINDA IORIZZO, LINDA IORIZZO Institute of Clinical Sciences, Lund University, Lund Department of Obstetrics and Gynecology, Skåne University Hospital, LundSearch for more papers by this authorULF JAKOBSSON, ULF JAKOBSSON Centre for Primary Health Care Research, Faculty of Medicine, Lund University, Lund, SwedenSearch for more papers by this author First published: 05 February 2011 https://doi.org/10.1111/j.1600-0412.2011.01085.xCitations: 46 Correspondence Pia Teleman, Department of Obstetrics and Gynecology, Skåne University Hospital/Lund, 221 85 Lund, Sweden. E-mail: pia.teleman@med.lu.se Conflict of interest The authors have stated explicitly that there are no conflicts of interest in connection with this article. AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract Objective. To psychometrically evaluate the Swedish translations of the short forms of the Pelvic Floor Impact Questionnaire (PFIQ-7), Pelvic Floor Distress Inventory (PFDI-20) and Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12). Design and Setting. Cross-sectional design, University hospital. Sample. Forty-four patients awaiting prolapse surgery. Methods. The dual-panel translation method followed by an evaluation of validity and reliability in prolapse patients. Main Outcome Measures. Construct, convergent and discriminant validity, reliability via test–retest and internal consistency. Results. Item response rates were high (range 95.5–100%) for PFIQ-7 and PFDI-20. The corrected item–total correlations showed acceptable construct validity for PFIQ-7 (r=0.338–0.826) but low for PFDI-20 (r=0.116–0.581) and PISQ-12 (r=0.024–0.735). Acceptable convergent validity was found in all three instruments, with a negative correlation with the SF-12. There were no floor or ceiling effects in the three instruments. In the test–retest analysis, intraclass correlation coefficients were significant (r=0.888–0.943). Cronbach's α varied between 0.57 and 0.94. Conclusion. This is the first validated translation of the PFIQ-7, PFDI-20 and PISQ-12 in Swedish. All three instruments indicated acceptable psychometric properties. Abbreviations: PFDI Pelvic Floor Distress Inventory PFIQ Pelvic Floor Impact Questionnaire PISQ Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire POP pelvic organ prolapse POPDI Pelvic Organ Prolapse Distress Inventory UIQ Urinary Impact Questionnaire CRAIQ Colo-rectal-anal Impact Questionnaire POPIQ Pelvic Organ Prolapse Impact Questionnaire POPDI Pelvic Organ Prolapse Distress Inventory CRADI Colo-rectal-anal Distress Inventory UDI Urinary Distress Inventory Introduction Pelvic organ prolapse (POP) is one of the most common problems a gynecologist meets in his/her practice. In spite of this, until recent years there have been few and incomplete ways to evaluate what symptoms are genuinely connected to objective findings and, furthermore, which of these are relieved by surgical or conservative treatment. We also need to evaluate negative side-effects and complications from surgery, including sexual function impairment. There are still no validated questionnaires regarding POP symptoms in Swedish. Tegerstedt et al. (1) have constructed a questionnaire in Swedish, but this is for identifying prolapse symptoms in population studies, not to evaluate the degree of inconvenience. Our aim was to validate a Swedish translation of internationally widely used instruments in order to be able to evaluate inconvenience, changes of inconvenience and treatment results in Swedish studies. The translated questionnaires would also facilitate comparisons with epidemiological studies and studies investigating POP treatment results from other countries, as well as participation in multinational studies. In 2001, the Pelvic Floor Impact Questionnaire (PFIQ), Pelvic Floor Distress Inventory (PFDI) and the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ) were constructed (2, 3). The PFIQ covers the impact of POP on daily life, the PFDI investigates the range of POP symptoms experienced by the patient and the grade of inconvenience they cause. The PISQ covers sexual function in heterosexual, sexually active women with POP and/or urinary incontinence. These three questionnaires have been used in numerous studies and have also been validated in their shorter versions, the PFIQ-7, PFDI-20 and PISQ-12 (4, 5). The original forms have been translated into and validated in Spanish (6, 7), the PISQ-12 in Turkish (8) and French (9), and the short forms in Arabic (10). Material and methods The dual-panel translation method was used (11). The professionals were one urogynecologist, one bilingual gynecologist in training, one nurse/PhD specialized in urinary tract symptoms in the elderly and one researcher/statistician specialized in psychometric methods. The translated version of the three instruments was presented to four lay persons, who were middle-aged to elderly women (not patients) with an education ranging from compulsory school to high university degrees. Some minor revisions were made based upon their comments. A test–retest was made by 44 native Swedish-speaking patients waiting for prolapse surgery. The SF12 questionnaire, which has been validated and used for many years in Swedish, was sent together with the test questionnaires. The women were asked to give personal comments on the wording of the questionnaires. When the filled-in questionnaires arrived, the retest questionnaires were sent out. The women were asked to fill in the retest questionnaire one to two weeks after the first one. The study was approved by the Ethical committe of Lund University Hospital (2009/304). The patients gave their signed consent. Statistical and data analysis The instrument was tested for construct validity (including discriminant and convergent validity) and reliability (12, 13). Validity was evaluated in terms of construct validity, through analysis of item response rate, floor and ceiling effects, and corrected item–total correlations. Item response rate was calculated as the number/percentage of respondents who had completed all items in the total instrument as well as in the subscales. A figure of 90% and above is considered as satisfactory. The proportion of floor and ceiling effects (i.e. people obtaining minimum and maximum scores, respectively) was studied among the subscales. The corrected item–total correlations (i.e. the correlation between each item and the total score of the remaining items in the hypothesized scale) should be 0.30 or greater to be considered as acceptable and interpreted as evidence supporting convergent validity. Convergent and discriminant validity were assessed by investigating intercorrelation between the subscales, using Spearman's rank order correlation, between the different instruments/subscales, as well as correlation between the instruments/subscales and the SF-12 instrument. Reliability was evaluated by means of a test–retest analysis and calculation of internal consistency. The test–retest was done at a two-week interval and assessed with intraclass correlations, while internal consistency was measured by means of Cronbach's α (14). The α values preferably range between 0.7 and 0.9 even if figures as low as 0.6 may be acceptable (12). Values of α lower than 0.7–0.6 indicate too high heterogeneity and values higher than 0.9 indicate that the items may be too similar. Some of the items in the PISQ-12 instrument were revised so that all items ranged from positive to negative replies before the analyses (e.g. calculation of summary scores, correlations and Cronbach's α) were performed. All data were analysed using SPSS for Windows 15.0 (SPSS Inc., Chicago, IL, USA). For the translated questionnaire documents: see Appendicies S1-S3. Results The test questionnaires were filled in by 44 patients, of whom 25 filled in the PISQ-12 as completely as needed for evaluation, i.e. at least 10 of the 12 questions. The patients were 39–74 years old, and represented prolapse in all compartments. Three patients filled in the first but not the second questionnaire; one of them moved without changing her address, and too much time elapsed before we found out. The other two declined to fill in the retest. Five patients immediately returned their retest after a reminder. The response rates for each item were high (range 95.5–100%) for PFIQ-7 and PFDI-20, and factor scores could be calculated (without any imputations) in 95.5% of cases for UIQ-7 (Urinary Impact Questionnaire), 97.7% of cases for CRAIQ-7 (Colo-rectal-anal Impact Questionnaire), 93.2% of cases for POPIQ-7 (Pelvic Organ Prolapse Impact Questionnaire), 95.5% of cases for POPDI-6 (Pelvic Organ Prolapse Distress Inventory), 100% of cases for CRADI-8 (Colo-rectal-anal Distress Inventory) and 93.2% of cases for UDI-6 (Urinary Distress Inventory). Regarding the PISQ-12, 25 of the 44 patients responded to the questionnaire (57% response rate), and the item response rate for the PISQ-12 ranged between 61.4 and 65.9%. Analyses of floor and ceiling effects showed no such problems for the three instruments. For PFDI-20 and PISQ-12, no respondents scored either the minimum or the maximum value of the scale, while for the PFIQ-7 instrument, four respondents (9.1%) reached the minimum value of zero. The corrected item–total correlations indicated that only PFIQ-7 had acceptable construct validity. The correlations were r=0.598–0.763 for UIQ-7, r=0.446–0.847 for CRAIQ-7, r=0.568–0.812 for POPIQ-7 and r=0.338–0.826 for the total instrument (PFIQ-7). The item–total correlations were much lower for PFDI-20 (r=0.116–0.581) and PISQ-12 (r=0.024–0.735); hence they cannot be seen to support construct validity for these instruments completely. In the PFDI-20, it was item numbers 2 and 3 that had r-values below 0.2, item number 14 had an r-value of 0.268, and all other r-values were above 0.3. In the PISQ-12 instrument, it was only item numbers 10 and 11 that had r-values around zero; all other items had r≥0.25. Correlation between the three instruments ranged between 0.484 and 0.695, and between 0.155 and 0.832 for the three instruments including the subscales (Table 1). Acceptable convergent validity in PFIQ-7 and PFDI-20 for all subscales correlated well within each instrument's summary score (r=0.729–0.832), as well as with similar measures/subscales. PISQ-12 only had significant correlations with PFDI-20 and the subscale POPDI-6. All three instruments had negative correlations with the two subscales in SF-12, which indicated acceptable construct validity (Table 1). In the test–retest analysis of the items, all intraclass correlations were significant (p<0.001) and varied between 0.888 and 0.943, thus indicating good test–retest reliability (Table 2). Internal consistency was measured by means of Cronbach's α, and the values for the five factors ranged between 0.57 and 0.94 (Table 1). Only POPDI-6 had α values below 0.70, indicating low homogeneity (Table 2). Table 1. Results from the analysis of convergent validity, i.e. correlation between the three instruments (including subscales) and SF-12. SF-12 (PCS) SF-12 (MCS) PFIQ-7 UIQ-7 CRAIQ-7 POPIQ-7 PFDI-20 POPDI-6 CRADI-8 UDI-6 PISQ-12 SF-12 (PCS) — SF-12 (MCS) 0.211 — PFIQ-7 −0.698* −0.444* — UIQ-7 −0.575* −0.124 0.777* — CRAIQ-7 −0.316* −0.470* 0.729* 0.386* — POPIQ-7 −0.825* −0.398* 0.832* 0.596* 0.399* — PFDI-20 −0.409* −0.412* 0.695* 0.678* 0.636* 0.480* — POPDI-6 −0.554* −0.485* 0.688* 0.554* 0.485* 0.680* 0.807* — CRADI-8 −0.124 −0.335* 0.452* 0.263 0.727* 0.155 0.754* 0.430* — UDI-6 −0.435* −0.185 0.524* 0.762* 0.301 0.371* 0.805* 0.582* 0.359* — PISQ-12 −0.515* −0.324 0.561* 0.351 0.362 0.341 0.484* 0.433* 0.219 0.348 — Note: Significant (*p≤ 0.05) correlations are indicated in the correlation matrix. The UIQ-7 (Urinary Impact Questionnaire), CRAIQ-7 (Colo-rectal-anal Impact Questionnaire) and POPIQ-7 (Pelvic Organ Prolapse Impact Questionnaire are subscales of the PFIQ-7 (Pelvic Floor Impact Questionnaire). The POPDI-6 (Pelvic Organ Prolapse Distress Inventory), CRADI-8 (Colo-rectal-anal Distress Inventory) and UDI-6 (Urinary Distress Inventory) are subscales of the PFDI-20 (Pelvic Floor Distress Inventory). Table 2. Results from the analyses for reliability (test–retest and internal consistency), for each instrument and subscale. Test mean (SD), range Retest mean (SD) Intraclass correlation (95% CI) p-Value for intraclass correlation Cronbach's α Test Retest PFIQ-7 66.2 (54.2), 0.0–223.8 60.4 (57.7), 0.0–228.6 0.906 (0.822–0.952) <0.001 0.925 0.942 UIQ-7 20.1 (20.9), 0.0–85.7 19.3 (22.8), 0.0–95.2 0.904 (0.824–0.949) <0.001 0.896 0.928 CRAIQ-7 19.5 (22.5), 0.0–100.0 16.7 (23.0), 0.0–100.0 0.894 (0.806–0.943) <0.001 0.887 0.923 POPIQ-7 26.7 (22.5), 0.0–76.2 24.8 (24.2), 0.0–85.7 0.906 (0.825–0.950) <0.001 0.885 0.924 PFDI-20 120.1 (54.1), 25.0–253.1 114.7 (55.1), 33.3–266.7 0.932 (0.866–0.967) <0.001 0.841 0.842 POPDI-6 47.7 (19.8), 8.3–87.5 48.4 (21.4), 8.3–87.5 0.888 (0.795–0.940) <0.001 0.569 0.637 CRADI-8 31.8 (21.9), 0.0–78.1 28.0 (21.9), 0.0–87.5 0.926 (0.860–0.961) <0.001 0.787 0.782 UDI-6 40.5 (24.8), 0.0–95.8 36.6 (25.9), 0.0–91.7 0.924 (0.850–0.962) <0.001 0.737 0.769 PISQ-12 16.1 (6.2), 3.0–28.0 16.0 (6.9), 3.0–29.0 0.943 (0.869–0.976) <0.001 0.712 0.779 Discussion The PFIQ, PFID and PISQ are proven to be valid and reliable condition-specific questionnaires in the original language, and are now among the most commonly used instruments for measuring quality of life and symptom inconvenience from pelvic organ prolapse and incontinence. As they are sensitive to change, they are applicable for epidemiological studies, as well as for evaluating results of treatment. Our aim to validate these questionnaires originates in a wish to have sound psychometric instruments for Swedish studies and maybe also to be able to compare our results with those of studies carried out in other countries. The psychometric evaluation of the three instruments did in general show acceptable psychometric properties. The response rate was high for all instruments except PISQ-12, with reasons discussed below. There were no floor and ceiling effects for any of the three instruments, and the results showed acceptable reliability. We chose the dual-panel translation method to avoid the limitation of adapting the translation for backtranslation. It is our view that the traditional methods such as 'forward–backward translation' or 'forward only' translation do not necessarily imply that the questionnaire is easily understood by a lay person. An enrichment of our group with one or more bilingual professionals, preferably persons who had been working in English-speaking countries, would have made our work easier and maybe more accurate. In Sweden, it is not customary for lay men to use the Latin words for different anatomical structures; it is possible that this might lead to misunderstandings. Cultural aspects have an influence on the relevance of questionnaires regarding the impact of symptoms on daily life. In the Arabic version, a question regarding influence on prayer has been added to the PFIQ. We find that a question regarding the influence of POP symptoms on the ability to fulfil professional tasks, i.e. going to work, is needed. Asking solely about household chores does not reflect modern lifestyles. The fact that the PISQ only covers women who are sexually active in a heterosexual relationship does not seem unproblematic. We believe that this is the reason for the relatively low response rate for the PISQ-12 compared with the other questionnaires. Using the PISQ-12 does not provide information on whether there is an increase or decrease in sexual activity following POP treatment. Adding the Lemack and Zimmern questionnaire (15) could be an option. A more general question, using a Likert scale, regarding the patient's experience of her sex life in relation to her POP and following treatment would also be possible. As we have validated the questionnaire specifically in patients planned for POP surgery, thus defined as having symptoms from their prolapse, this should preferably be further evaluated in a larger number of women. The colorectal–anal and urinary distress sections of the PFDI could also be further adjusted by comparing with other instruments validated in Swedish in patients, seeking specifically for symptoms in these areas. In conclusion, we find our translation of the short forms of the PFIQ, PFDI and PISQ to be feasible in a Swedish setting, and that all three instruments seem psychometrically valid. Our aim is to test these instruments in a larger setting to be able to make further adjustments if necessary. Acknowledgements Part of this study was funded by the Zoégas foundation, Helsingborg, Sweden. Supporting Information Appendix S1. Frågeformulär om framfall/urininkontinens och sexuell funktion (PISQ-12). Appendix S2. Bäckenbottenbesvär och dess inverkan på Ditt dagliga liv PFIQ-7. Appendix S3. Kartläggning av besvär från bäcken botten (PFDI-20). Filename Description AOG_1085_sm_AppendixS1-3.pdf63.3 KB Supporting info item Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. References 1 Tegerstedt G, Miedel A, Maehle-Schmidt M, Nyren O, Hammarström M. A short-form questionnaire identified genital organ prolapse. Clin Epidemiol. 2005; 58: 41– 6. CrossrefPubMedWeb of Science®Google Scholar 2 Barber MD, Kuchibhatla MN, Pieper CF, Bump RC. Psychometric evaluation of 2 comprehensive condition-specific quality of life instruments for women with pelvic floor disorders. Am J Obstet Gynecol. 2001; 185: 1388– 95. CrossrefCASPubMedWeb of Science®Google Scholar 3 Rogers R, Kammerer-Doak D, Villareal A, Coates K, Qualls C. A new instrument to measure sexual function in women with urinary incontinence or pelvic organ prolapse. Am J Obstet Gynecol. 2001; 184: 552– 8. CrossrefCASPubMedWeb of Science®Google Scholar 4 Barber MD, Walters MD, Bump RC. Short forms of two condition-specific quality-of-life questionnaires for women with pelvic floor disorders (PFDI-20 and PFIQ-7). Am J Obstet Gynecol. 2005; 193: 103– 13. CrossrefCASPubMedWeb of Science®Google Scholar 5 Rogers R, Coates K, Kammerer-Doak D, Khalsa S, Qualls C. A short form of the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12). Int Urogynecol J. 2003; 14: 164– 8. CrossrefPubMedWeb of Science®Google Scholar 6 Omotosho TB, Hardart A, Rogers R, Schaffer JI, Kobak WH, Romero AA. Validation of Spanish versions of the Pelvic Floor Distress Inventory (PFDI) and Pelvic Floor Impact Questionnaire (PFIQ): a multicenter validation randomized study. Int Urogynecol J. 2009; 20: 623– 39. CrossrefPubMedWeb of Science®Google Scholar 7 Young AE, Fine PM, McGrery R, Wren PA, Richter HE, Brubaker L, et al. Spanish language translation of pelvic floor disorder instruments. Int Urogynecol J. 2007; 18: 1171– 8. CrossrefPubMedWeb of Science®Google Scholar 8 Cam C, Sancak P, Karahan N, Sancak A, Celik C, Karateke A. Validation of the short form of the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12) in a Turkish population. Eur J Obstet Reprod Biol. 2009; 146: 104– 7. CrossrefPubMedWeb of Science®Google Scholar 9 De Tayrac R, Mathé ML, Bader G, Deffieux X, Fazel A, Fernandez H. [Development of a linguistically validated French version of two short-form, condition-specific quality of life questionnaires for women with pelvic floor disorders (PFDI-20 and PFIQ-7)]. (Article in French.) J Gynecol Obstet Biol Reprod. 2007; 36: 738– 48. CrossrefCASPubMedGoogle Scholar 10 El-Azab A, Abd-Elsayed AA, Imam HMK. Patient reported and anatomical outcomes after surgery for pelvic organ prolapse. Neurourol Urodyn. 2009; 28: 219– 24. Wiley Online LibraryPubMedWeb of Science®Google Scholar 11 Acquadro C, Conway K, Hareendran A, Aaronson N. Literature review of methods to translate heath-related quality of life questionnaires for use in multinational clinical trials. Value in Health. 2008; 11: 509– 21. Wiley Online LibraryCASPubMedWeb of Science®Google Scholar 12 Nunnally JC, Bernstein IH. Psychometric theory. 3rd edn. New York : McGraw-Hill Inc., 1994. Google Scholar 13 Streiner DL, Norman GR. Health measurement scales. A practical guide to their development and use. 3rd edn. Oxford : Oxford University Press, 2003. Google Scholar 14 Cronbach LJ. Coefficient alpha and the internal structures of tests. Psychometrika 1951; 3: 297– 334. CrossrefGoogle Scholar 15 Lemack GE, Zimmern PE. Sexual function after vaginal surgery for stress incontinence: results of a mailed questionnaire. Urology. 2000; 56: 223– 7. CrossrefCASPubMedWeb of Science®Google Scholar Citing Literature Volume90, Issue5May 2011Pages 483-487 ReferencesRelatedInformation
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