J Wound Ostomy Continence Nurs. 2014;41(5):467-472. Published by Lippincott Williams & Wilkins
CONTINENCE CARE
A Simulation Comparing the Cost-effectiveness of Adult Incontinence Products Kelly Yamasato
Bliss Kaneshiro
■ ABSTRACT
PURPOSE: To compare leak point volumes and costeffectiveness of a variety of adult incontinence products. METHODS: Adult incontinence products were purchased from local retail stores and categorized into moderate absorbency pads, moderate absorbency briefs, maximum absorbency pads, and maximum absorbent briefs. The leak point for each product was determined by applying fluid to the pad until the first drop of leakage from the pad or brief occurred. Cost-effectiveness was calculated by dividing the cost per product by the amount of fluid absorbed prior to the leak point. The leak points and cost-effectiveness of incontinence products were compared within and between categories. RESULTS: Significant differences in leak point volumes were present within all product categories except moderate absorbency pads. When comparing product categories, moderate absorbency pads were the least cost-effective, followed by maximum absorbency pads and absorbent briefs (P < .01). CONCLUSIONS: As a group, absorbent briefs are more cost-effective than incontinence pads, although products of similar absorbency category and design demonstrated varying leak points and cost-effectiveness. These findings may influence physician assessment of urinary incontinence as well as patient selection of incontinence products. KEY WORDS: absorbency, cost-effectiveness, incontinence, incontinence briefs, incontinence pads, leakage
■ Introduction Urinary incontinence (UI) is a common and costly condition that exerts a significant impact on health-related quality of life.1,2 In 2005, Subak and colleagues3 estimated individuals with severe UI spend approximately US$900 per year to treat this condition. Although some of this expenditure goes toward medications, a significant portion is used to pay for incontinence pads and absorbent
Ian A. Oyama
briefs, which most patients with incontinence use at least for some period of time.4,5 Multiple factors, such as leakage, wetness, and odor, may influence a user to change his or her incontinence product.6 However, individuals who use pads and absorbent briefs frequently cite protection from urine leakage as the most desirable quality in these products.6,7 Therefore, the volume at which leakage occurs, also referred to as its leak point, is an objective measure that can be used to assess the cost-effectiveness of a given incontinence product. Multiple test models have been developed to assess the absorption capacity of incontinence products.8,9 For example, the TEFO (Swedish Institute for Textile Research) test measures the absorption capacity of discs of the composite product and extrapolates that absorption to estimate the absorption of the entire pad or brief.7 The Rothwell Method assesses weight change before and after a product is saturated in normal saline.8 Both have demonstrated strong clinical correlation for leakage performance.7 Research on product cost-effectiveness based on leak point volumes for incontinence products is sparse. The purpose of this study was to determine and compare the leak points of various commercially available incontinence pads and absorbent briefs and compare the cost-effectiveness of these products in relation to leakage performance.
Kelly Yamasato, MD, Clinical instructor, Department of Obstetrics, Gynecology, and Women’s Health. University of Hawaii John A Burns School of Medicine, Honolulu. Bliss Kaneshiro, MD, MPH, Associate professor, Department of Obstetrics, Gynecology, and Women’s Health. University of Hawaii John A Burns School of Medicine, Honolulu. Ian A. Oyama, MD, MBA, Department of Obstetrics, Gynecology, and Women’s Health. University of Hawaii John A Burns School of Medicine, Honolulu. The authors declare no conflict of interest. Correspondence: Kelly Yamasato, MD, 1319 Punahou St, 824, Honolulu, HI 96826 ([email protected]). DOI: 10.1097/WON.0000000000000045
Copyright © 2014 by the Wound, Ostomy and Continence Nurses Society™
J WOCN
■ September/October 2014 467
Copyright © 2014 Wound, Ostomy and Continence Nurses Society™. Unauthorized reproduction of this article is prohibited.
JWOCN-D-13-00046_LR 467
26/08/14 6:43 PM
468
Yamasato et al
■ Methods Incontinence products were purchased at full retail price from local retail stores and kept in their original packaging until they were used in the study. Light absorbency pads were excluded as our simulation was designed to replicate a severe incontinence episode for which light absorbency products are not indicated. Products were then grouped by product label into 4 categories: (1) moderate absorbency pads, (2) maximum absorbency pads, (3) moderate absorbency briefs, and (4) maximum absorbency briefs. These categories were created to represent the range of incontinence product design and absorbency levels available for severe urinary incontinence in the standard retail setting. Three products from each category were randomly chosen to include a total of 12 incontinence products. Each pad or brief was suspended at its longitudinal ends at an approximately 120º arc to simulate pad position during use in women.10 An open syringe was held so that the tip was adjacent to the surface of the pad or diaper. Water was dropped onto the center of each pad or diaper through the syringe at a rate of 15 mL per second. The flow rate of 15 mL per second was chosen as it approaches the mean urine flow rate during the void of a 50-year-old woman.11 The leak point of each pad or brief was determined to be the volume absorbed by the product before the first drop of fluid fell from the pad. Measurements were repeated 20 times for each product. Based on preliminary data with incontinence products using this technique, a sample size of 20 per product provided 80% power to detect a difference of 185 mL (SD = 175 mL) in heavy absorbency products and 232 mL (SD = 140 mL) in medium absorbency products with a significance of 0.05.
Data Analysis Leak point volume, cost per product, and cost-effectiveness were compared for the 4 product categories using analysis of variance (ANOVA). The cost in cents per 100 mL absorbed ratio was calculated to assess cost-effectiveness. Within each product category, pairwise comparisons with a Bonferroni adjustment were made for the leak points and cost-effectiveness of each product. All analyses were performed with Statistical Program for Social Sciences (SPSS 16.0 for Windows; SPSS Inc, Chicago, Illinois).
■ Results The leak point volumes of the 12 incontinence products included in this study are presented in Table 1. Brand names of the 12 products are listed in the Appendix. Pads marketed as moderate absorbency had mean leak points between 100 and 200 mL and those marketed as maximum absorbency had mean leak points between 200 and 400 mL. The mean leak point volumes of moderate and maximum absorbency briefs overlapped considerably with mean leak point volumes ranging between 250 and 850 mL.
J WOCN
■ September/October 2014
TABLE 1.
Mean Leak Points of Incontinence Products
Product
Leak Point Volumes, Mean (SD), in mL
Moderate absorbency pads Pad A moderate
207.90 (35.39)
Pad B moderate
96.55 (67.00)
Pad C moderate
159.75 (15.62)
Mean for all moderate absorbency pads
154.73 (63.58)
Maximum absorbency pads Pad D maximum
194.50 (36.54)
Pad E maximum
199.85 (39.51)
Pad F maximum
437.15 (111.28)
Mean for all maximum absorbency pads
277.17 (133.94)
Moderate absorbency briefs Brief A moderate
683.85 (131.09)
Brief B moderate
353.25 (116.08)
Brief C moderate
761.60 (84.10)
Mean for all medium absorbency briefs
599.57 (209.82)
Maximum absorbency briefs Brief D maximum
673.25 (141.33)
Brief E maximum
850.75 (209.68)
Brief F maximum
256.60 (57.24)
Mean for all maximum absorbency briefs
593.53 (291.05)
Table 2 presents pairwise comparisons of the leak point volumes by products individually and products grouped by absorbency and design. No significant differences between the mean leak point volumes of moderate absorbency pads emerged when pairwise comparisons were used to compare products. Pad F maximum pads absorbed significantly more than Pad D (P < .001) or Pad E maximum pads (P < .001). Brief B moderate briefs demonstrated a significantly lower leak point volume than Brief C moderate briefs and Brief A moderate briefs (P < .001). Pairwise comparisons showed that Brief F maximum briefs had a significantly lower leak point than Brief D maximum briefs (P < .001) and Brief E maximum briefs (P < .001). Brief D maximum briefs also absorbed significantly less than Brief E maximum briefs (P < .001). When products were grouped by absorbency and design, moderate absorbency pads had a significantly lower leak point than maximum pads (P < .01). Maximum and moderate absorbency briefs had significantly higher leak point volumes than maximum and moderate absorbency pads (P < .001). However, analysis revealed no significant difference between the leak point volumes of maximum and moderate absorbency briefs (P = 1.00).
Copyright © 2014 Wound, Ostomy and Continence Nurses Society™. Unauthorized reproduction of this article is prohibited.
JWOCN-D-13-00046_LR 468
26/08/14 6:43 PM
J WOCN
■ Volume 41/Number 5
Yamasato et al
469
TABLE 2.
Pairwise Comparisons of Mean Leak Points Mean Difference, mL
95% CI of Difference
P
Pad A moderate versus Pad B moderate
111.35
0.63, 222.07
.05
Pad A moderate versus Pad C moderate
48.15
−62.57, 158.87
1.00
Pad B moderate versus Pad C moderate
−63.20
−173.92, 47.52
1.00
Pad D maximum versus Pad E maximum
−5.35
−116.07, 105.37
1.00
Pad D maximum versus Pad F maximum
−242.65
−353.37, −131.93
CONTINENCE CARE
A Simulation Comparing the Cost-effectiveness of Adult Incontinence Products Kelly Yamasato
Bliss Kaneshiro
■ ABSTRACT
PURPOSE: To compare leak point volumes and costeffectiveness of a variety of adult incontinence products. METHODS: Adult incontinence products were purchased from local retail stores and categorized into moderate absorbency pads, moderate absorbency briefs, maximum absorbency pads, and maximum absorbent briefs. The leak point for each product was determined by applying fluid to the pad until the first drop of leakage from the pad or brief occurred. Cost-effectiveness was calculated by dividing the cost per product by the amount of fluid absorbed prior to the leak point. The leak points and cost-effectiveness of incontinence products were compared within and between categories. RESULTS: Significant differences in leak point volumes were present within all product categories except moderate absorbency pads. When comparing product categories, moderate absorbency pads were the least cost-effective, followed by maximum absorbency pads and absorbent briefs (P < .01). CONCLUSIONS: As a group, absorbent briefs are more cost-effective than incontinence pads, although products of similar absorbency category and design demonstrated varying leak points and cost-effectiveness. These findings may influence physician assessment of urinary incontinence as well as patient selection of incontinence products. KEY WORDS: absorbency, cost-effectiveness, incontinence, incontinence briefs, incontinence pads, leakage
■ Introduction Urinary incontinence (UI) is a common and costly condition that exerts a significant impact on health-related quality of life.1,2 In 2005, Subak and colleagues3 estimated individuals with severe UI spend approximately US$900 per year to treat this condition. Although some of this expenditure goes toward medications, a significant portion is used to pay for incontinence pads and absorbent
Ian A. Oyama
briefs, which most patients with incontinence use at least for some period of time.4,5 Multiple factors, such as leakage, wetness, and odor, may influence a user to change his or her incontinence product.6 However, individuals who use pads and absorbent briefs frequently cite protection from urine leakage as the most desirable quality in these products.6,7 Therefore, the volume at which leakage occurs, also referred to as its leak point, is an objective measure that can be used to assess the cost-effectiveness of a given incontinence product. Multiple test models have been developed to assess the absorption capacity of incontinence products.8,9 For example, the TEFO (Swedish Institute for Textile Research) test measures the absorption capacity of discs of the composite product and extrapolates that absorption to estimate the absorption of the entire pad or brief.7 The Rothwell Method assesses weight change before and after a product is saturated in normal saline.8 Both have demonstrated strong clinical correlation for leakage performance.7 Research on product cost-effectiveness based on leak point volumes for incontinence products is sparse. The purpose of this study was to determine and compare the leak points of various commercially available incontinence pads and absorbent briefs and compare the cost-effectiveness of these products in relation to leakage performance.
Kelly Yamasato, MD, Clinical instructor, Department of Obstetrics, Gynecology, and Women’s Health. University of Hawaii John A Burns School of Medicine, Honolulu. Bliss Kaneshiro, MD, MPH, Associate professor, Department of Obstetrics, Gynecology, and Women’s Health. University of Hawaii John A Burns School of Medicine, Honolulu. Ian A. Oyama, MD, MBA, Department of Obstetrics, Gynecology, and Women’s Health. University of Hawaii John A Burns School of Medicine, Honolulu. The authors declare no conflict of interest. Correspondence: Kelly Yamasato, MD, 1319 Punahou St, 824, Honolulu, HI 96826 ([email protected]). DOI: 10.1097/WON.0000000000000045
Copyright © 2014 by the Wound, Ostomy and Continence Nurses Society™
J WOCN
■ September/October 2014 467
Copyright © 2014 Wound, Ostomy and Continence Nurses Society™. Unauthorized reproduction of this article is prohibited.
JWOCN-D-13-00046_LR 467
26/08/14 6:43 PM
468
Yamasato et al
■ Methods Incontinence products were purchased at full retail price from local retail stores and kept in their original packaging until they were used in the study. Light absorbency pads were excluded as our simulation was designed to replicate a severe incontinence episode for which light absorbency products are not indicated. Products were then grouped by product label into 4 categories: (1) moderate absorbency pads, (2) maximum absorbency pads, (3) moderate absorbency briefs, and (4) maximum absorbency briefs. These categories were created to represent the range of incontinence product design and absorbency levels available for severe urinary incontinence in the standard retail setting. Three products from each category were randomly chosen to include a total of 12 incontinence products. Each pad or brief was suspended at its longitudinal ends at an approximately 120º arc to simulate pad position during use in women.10 An open syringe was held so that the tip was adjacent to the surface of the pad or diaper. Water was dropped onto the center of each pad or diaper through the syringe at a rate of 15 mL per second. The flow rate of 15 mL per second was chosen as it approaches the mean urine flow rate during the void of a 50-year-old woman.11 The leak point of each pad or brief was determined to be the volume absorbed by the product before the first drop of fluid fell from the pad. Measurements were repeated 20 times for each product. Based on preliminary data with incontinence products using this technique, a sample size of 20 per product provided 80% power to detect a difference of 185 mL (SD = 175 mL) in heavy absorbency products and 232 mL (SD = 140 mL) in medium absorbency products with a significance of 0.05.
Data Analysis Leak point volume, cost per product, and cost-effectiveness were compared for the 4 product categories using analysis of variance (ANOVA). The cost in cents per 100 mL absorbed ratio was calculated to assess cost-effectiveness. Within each product category, pairwise comparisons with a Bonferroni adjustment were made for the leak points and cost-effectiveness of each product. All analyses were performed with Statistical Program for Social Sciences (SPSS 16.0 for Windows; SPSS Inc, Chicago, Illinois).
■ Results The leak point volumes of the 12 incontinence products included in this study are presented in Table 1. Brand names of the 12 products are listed in the Appendix. Pads marketed as moderate absorbency had mean leak points between 100 and 200 mL and those marketed as maximum absorbency had mean leak points between 200 and 400 mL. The mean leak point volumes of moderate and maximum absorbency briefs overlapped considerably with mean leak point volumes ranging between 250 and 850 mL.
J WOCN
■ September/October 2014
TABLE 1.
Mean Leak Points of Incontinence Products
Product
Leak Point Volumes, Mean (SD), in mL
Moderate absorbency pads Pad A moderate
207.90 (35.39)
Pad B moderate
96.55 (67.00)
Pad C moderate
159.75 (15.62)
Mean for all moderate absorbency pads
154.73 (63.58)
Maximum absorbency pads Pad D maximum
194.50 (36.54)
Pad E maximum
199.85 (39.51)
Pad F maximum
437.15 (111.28)
Mean for all maximum absorbency pads
277.17 (133.94)
Moderate absorbency briefs Brief A moderate
683.85 (131.09)
Brief B moderate
353.25 (116.08)
Brief C moderate
761.60 (84.10)
Mean for all medium absorbency briefs
599.57 (209.82)
Maximum absorbency briefs Brief D maximum
673.25 (141.33)
Brief E maximum
850.75 (209.68)
Brief F maximum
256.60 (57.24)
Mean for all maximum absorbency briefs
593.53 (291.05)
Table 2 presents pairwise comparisons of the leak point volumes by products individually and products grouped by absorbency and design. No significant differences between the mean leak point volumes of moderate absorbency pads emerged when pairwise comparisons were used to compare products. Pad F maximum pads absorbed significantly more than Pad D (P < .001) or Pad E maximum pads (P < .001). Brief B moderate briefs demonstrated a significantly lower leak point volume than Brief C moderate briefs and Brief A moderate briefs (P < .001). Pairwise comparisons showed that Brief F maximum briefs had a significantly lower leak point than Brief D maximum briefs (P < .001) and Brief E maximum briefs (P < .001). Brief D maximum briefs also absorbed significantly less than Brief E maximum briefs (P < .001). When products were grouped by absorbency and design, moderate absorbency pads had a significantly lower leak point than maximum pads (P < .01). Maximum and moderate absorbency briefs had significantly higher leak point volumes than maximum and moderate absorbency pads (P < .001). However, analysis revealed no significant difference between the leak point volumes of maximum and moderate absorbency briefs (P = 1.00).
Copyright © 2014 Wound, Ostomy and Continence Nurses Society™. Unauthorized reproduction of this article is prohibited.
JWOCN-D-13-00046_LR 468
26/08/14 6:43 PM
J WOCN
■ Volume 41/Number 5
Yamasato et al
469
TABLE 2.
Pairwise Comparisons of Mean Leak Points Mean Difference, mL
95% CI of Difference
P
Pad A moderate versus Pad B moderate
111.35
0.63, 222.07
.05
Pad A moderate versus Pad C moderate
48.15
−62.57, 158.87
1.00
Pad B moderate versus Pad C moderate
−63.20
−173.92, 47.52
1.00
Pad D maximum versus Pad E maximum
−5.35
−116.07, 105.37
1.00
Pad D maximum versus Pad F maximum
−242.65
−353.37, −131.93
