Factors Associated with Regional Adoption of Ureteroscopy in California from 2005 to 2016

Abstract

Purpose: To explore regional adoption of ureteroscopy (URS) over extracorporeal shockwave lithotripsy (SWL) in the state of California (CA) and to identify factors associated with this adoption over time.

Materials and methods: We used the California Office of Statewide Health Planning and Development (OSHPD) public data to identify URS and SWL procedures performed for renal and ureteral stones from 2005 to 2016. The level of analysis was the region wherein each procedure was performed, defined by the 19 CA labor market regions. OSHPD data were supplemented with the Area Health Resource File to provide information on regional characteristics. Generalized linear regression was used to determine procedural rates adjusted for age, gender and race. Choropleth time series maps were used to illustrate adoption of URS by region over time.

Results: A total of 328,795 URS and SWL procedures were identified from 2005 to 2016. The number of URS procedures surpassed the number of SWL procedures in 2011. Fourteen regions became URS predominant by 2016 and were characterized as having a higher per capita income, higher percentages with a college education and lower percentage of female heads-of-household (all p-values <0.05). A higher percentage of patients in these regions were male and had private or Medicare insurance (p = 0.03 for both).

Conclusions: From 2005 to 2016, most CA regions adopted URS as the primary renal and ureteral stone management strategy. These regions demonstrated characteristics of higher socioeconomic status compared to regions that remained SWL predominant. A better understanding of such differences in practice patterns will allow urologists to better negotiate for the capital expenditures required to conform to evolving standards of care and allow patients the ability to make more informed decisions on where they receive care.

Keywords: epidemiology; practice patterns; regional factors; shockwave lithotripsy; ureteroscopy.

FIG. 1.

Number of ureteroscopy and shockwave lithotripsy procedures reported to the California Office of Statewide Health Planning and Development for renal and ureteral stones from 2005 to 2016. The black line represents the total number of cases, while the gray line represents ureteroscopy procedures, and the dashed line represents shockwave lithotripsy procedures.

FIG. 2.

Time series choropleth map of the State of California, United States, illustrating the relative proportion of ureteroscopy to shockwave lithotripsy procedures reported to the California Office of Statewide Health Planning and Development for renal and ureteral stones from 2005 to 2016. The locations of urology residency programs are indicated with dots in the top left panel. Areas represented in blue perform ≥50% ureteroscopy, while areas in red perform <50% ureteroscopy with darker colors being further from 50% ureteroscopy procedures.

FIG. 3.

Caterpillar chart illustrating the relative proportion of ureteroscopy to shockwave lithotripsy procedures reported to the California Office of Statewide Health Planning and Development for renal and ureteral stones for 2005 (circle) and 2016 (triangle) after adjusting for age, race, and gender of the patients. California Labor Division Economic subregions were rank ordered by proportion of ureteroscopy procedures vs shockwave lithotripsy procedures in 2005; this order was maintained for 2016. Horizontal bars represent the standard error calculation.