Draft Research Plan
Chronic Kidney Disease: Screening
January 19, 2023
Recommendations made by the USPSTF are independent of the U.S. government. They should not be construed as an official position of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.
Abbreviation: CKD=chronic kidney disease.
- In asymptomatic adults without known chronic kidney disease (CKD),* what are the effects of screening for CKD vs. no screening on clinical outcomes?
- What are the harms of screening for CKD vs. no screening?
- What is the diagnostic accuracy of screening to identify adults with CKD stages 1–3?
- How does diagnostic accuracy vary in populations defined by race, ethnicity, age, and sex?
- Among adults with CKD stages 1–3,† what are the effects of monitoring for worsening kidney function, kidney damage, or both vs. no monitoring on clinical outcomes?
- Among adults with CKD stages 1–3,† what are the harms of monitoring for worsening kidney function, kidney damage, or both vs. no monitoring?
- Among adults with CKD stages 1–3,† what are the effects of treatment on likelihood of developing stage 4 or 5 CKD?
- Among adults with CKD stages 1–3,† what are the effects of treatment on clinical outcomes?
- Among adults with CKD stages 1–3,† what are the effects of treatment on harms?
*For screening, studies in which patients were selected on the basis of having conditions associated with CKD (e.g., hypertension, diabetes) are not eligible for inclusion. However, studies are not required to exclude patients with these conditions.
†For treatment, studies will not be restricted according to whether patients have screen- or non-screen-detected CKD, or whether patients are eligible for evaluated treatments for reasons other than CKD (e.g., presence of diabetes mellitus, hypertension, or dyslipidemia).
- What disparities are present in diagnosis of CKD and utilization of treatment, and what factors are associated with disparities?
- What is the effectiveness of interventions aimed at reducing disparities in persons with CKD?
- What are the harms of being labeled with a diagnosis of CKD stages 1–3?
To the extent possible, we plan to describe the participant characteristics and major intervention components of the included studies. Data on population characteristics will help us explore the degree to which the findings are broadly representative of the U.S. population, including individuals across age; sex and gender; racial, ethnic, and cultural identity; socioeconomic status; and geographic region. Evidence will be evaluated to determine if there are common components of efficacious interventions (e.g., diet approaches or medication dose), and to the extent possible, whether interventions tailored to specific groups tend to have larger effect sizes than those that are not tailored. As part of our effort to address health equity, we will search for and highlight interventions that demonstrate effectiveness in groups of individuals who historically have lower rates of screening and in traditionally stigmatized or underrepresented groups. Additionally, the proposed contextual questions are designed to address other important health equity considerations.
The Proposed Research Approach identifies the study characteristics and criteria that the Evidence-based Practice Center will use to search for publications and to determine whether identified studies should be included or excluded from the Evidence Review. Criteria are overarching as well as specific to each of the key questions.
|Populations||Adults age 18 years or older
KQs 1–3: Asymptomatic patients without known CKD and not selected on the basis of presence of diabetes mellitus or hypertension, with or without recognized risk factors for CKDKQs 4–8: Patients with screen-detected CKD or non-screen-detected CKD stages 1–3 (based on 2012 KDIGO or 2002 KDOQI definitions* or equivalent), including adults with diabetes mellitus or hypertension
|Screening tests and treatments not described as included|
|Comparisons||KQs 1, 2: Screening vs. no screening or usual care
KQs 3, 3a: Screening test vs. reference standard using an exogenous tool that measures kidney function directly
KQs 4, 5: Monitoring vs. no monitoring
|Comparisons not described as included|
|Outcomes||KQs 1, 4, 7:
KQs 1, 4, 6: Progression to stage 4 or stage 4/5 CKD
KQs 2, 5, 8:
KQs 3, 3a:
|Outcomes not described as included|
|Study Design||KQs 1, 2, 4–8: Trials and systematic reviews of trials
KQs 1, 2, 4, 5: Controlled observational studiesKQs 3, 3a: Studies reporting diagnostic accuracy
|Study designs not described as included|
|Study Quality||Good-quality or fair-quality; poor-quality only if better quality studies are lacking||KQs 6–8:
Abbreviations: CKD=chronic kidney disease; GFR=glomerular filtration rate; KDIGO=Kidney Disease Improving Global Outcomes; KDOQI=Kidney Disease Outcomes Quality Initiative.
KDOQI, 2002: Kidney damage for ≥3 months, as defined by structural or functional abnormalities of the kidney, with or without decreased GFR, manifest by either: pathological abnormalities or markers of kidney damage, including abnormalities in the composition of the blood or urine, or abnormalities in imaging tests and/or GFR <60 mL/min/1.73 m2 for ≥3 months.1
KDIGO, 2012: Either of the following present for >3 months: markers of kidney damage (one or more), including albuminuria (albumin excretion rate ≥30 mg/24 hours; albumin to creatinine ratio ≥30 mg/g [≥3 mg/mmol]), urine sediment abnormalities, electrolyte and other abnormalities due to tubular disorders, abnormalities detected by histology, structural abnormalities detected by imaging, or history of kidney transplantation and/or decreased GFR (GFR <60 mL/min/1.73 m2; GFR categories G3a-G5).2
1. National Kidney Foundation. K/DOQI Clinical practice guidelines for chronic kidney disease: evaluation, classification and stratification. Am J Kidney Dis. 2002;39(suppl 1):S1-S266.
2. KDIGO 2012 Clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney Int Suppl. 2013;3(1):136-150.