An interventional study of Surgery and Observation in Nephrolithiasis and Kidney Stone, sponsored by Children's Hospital of Philadelphia. Recruiting at 4 sites in United States. Open to participants aged 6 Years and older. Per ClinicalTrials.gov, last updated 2026-10-15.
Sponsored by Children's Hospital of Philadelphia · Not applicable, Interventional, and Treatment
The aims of the Observational Approach versus Surgical Intervention for Asymptomatic Stone (OASIS) trial are: 1) to determine whether observation compared to upfront surgery results in less healthcare-related life disruption due to kidney stones among children and adults with asymptomatic kidney stones; 2) to identify the groups benefiting the most from each strategy; and 3) to determine the preferences and values informing the choice between observation and upfront surgery.
A critical barrier to improving the health of the nearly 40 million Americans with kidney stone disease is the weak evidence base supporting the management of individuals with asymptomatic kidney stones. The proposed Observational Approach versus Surgical Intervention for Asymptomatic Stone (OASIS) randomized clinical trial answers the research question of whether observation or upfront surgery results in less life disruption from asymptomatic kidney stones for children and adults. The management options for patients with asymptomatic stones are 1) observation or 2) upfront surgical treatment, both of which are considered safe, part of usual care, widely accessible, and covered by insurance.
OASIS responds to the charge for well-designed Randomized Controlled Trials (RCT) from the Agency for Healthcare Research and Quality (AHRQ) systematic review on kidney stone disease management and ensures patient centeredness by examining outcomes that patients have identified as meaningful.
Intervention
Randomization to either:
Observational Cohort (Non-Randomized Cohort):
Up to 300 eligible subjects who are willing to consent to data collection but refuse randomization will be enrolled and followed for two years.
Study Design OASIS is a pragmatic randomized controlled superiority trial conducted at approximately 30 sites that participate in Patient Centered Outcomes Research Network (PCORnet). The trial will include an additional observational cohort for eligible subjects who decline randomization.
509 studies on the registry are indexed under Kidney Calculi; 146 are open to participants now.
This study's planned enrollment of 1,658 is above the median of 86 across 391 interventional studies indexed under Kidney Calculi.
Browse Kidney Calculi studies →Children's Hospital of Philadelphia is the lead sponsor of 489 studies on the registry; 90 are open to participants now.
Of its 28 completed or terminated interventional studies of FDA-regulated products, 22 (79%) have results posted.
Compared within Kidney Calculi, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Nephrolithiasis. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Asymptomatic, non-obstructive kidney stones measuring 4 to 10 mm (inclusive)
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Procedure: Surgery · Other: Observation
Procedure: Surgery · Other: Observation
Upfront surgery is the planned removal of asymptomatic stones and includes ureteroscopy and shockwave lithotripsy, which are routinely used in standard clinical care.
Observation is the surveillance of asymptomatic stones with periodic CT, ultrasound, or x-ray, and clinic visits.
Healthcare-related life disruption
Composite of: Stone-specific emergency department (ED)/urgent care visits, stone-specific hospitalizations and surgery for stones for new symptoms (Shockwave Lithotripsy (SWL) and Ureteroscopy (URS)) as reported via Patient Centered Outcomes Research Network (PCORnet) Common Data Model (CDM) query and participant self-report on REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Patient reported physical and emotional health (Pain Interference)
Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference (PI) is a standardized, self-reported assessment tool developed by the National Institutes of Health (NIH). It measures how much pain hinders a person's physical, mental, social, and recreational activities, as well as their sleep and enjoyment of life. It uses a standardized T-score (average is 50; standard deviation is 10) to reflect the level of disruption. Higher numbers mean more pain interference (pain is having a greater negative impact on your daily life, making it harder to participate in work, social, and physical activities). The study team is using the validated versions for adults (18 years and older at time of consent), children (ages 8-17 years at time of consent), and parent-proxy versions for caregivers of children ages (6-7 years at time of consent). This information will be captured via patient report in REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Patient reported physical and emotional health (Anxiety)
Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety is a standardized, self-reported assessment tool developed by the National Institutes of Health (NIH). It measures the severity of fear, worry, dread, hyperarousal, and physical stress symptoms over the past seven days on a 5-point scale (ranging from never to always). Raw scores are converted into a standardized T-score with an average of 50 and a standard deviation of 10. A higher T-score indicates a higher severity of anxiety. The study team is using validated versions for adults (18 years and older at time of consent), children (ages 8-17 years at time of consent), and parent-proxy versions for caregivers of children ages (6-7 years at time of consent). This information will be captured via patient report in REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Patient reported physical and emotional health (Stone Quality of Life)
The Wisconsin Stone Quality of Life questionnaire (WISQOL) is a disease-specific health-related quality of life (HRQOL) instrument designed to assess the impact on patients of stones in the urinary tract. Each item is scored on a 5-point Likert scale, yielding a total raw score of 28 to 140. Higher scores reflect a better health-related quality of life. Raw scores are typically converted to a standardized 0-100 scale. This information will be captured via patient report on REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Stone passage
Patient Reported Survey: Number of self-reported stone passages (A kidney stone episode is passing a stone that caused pain or other bothersome symptoms or having surgery to remove a stone.) This information will be captured via patient report on REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months. Reporting total after 2 years.
Lost productivity (Missed School)
Patient Reported Survey: Number of days the patient (for patients under 18 years old at time of consent) missed school due to kidney stones or kidney stone-related care (0 days, 1-2 days, 3-5 days, 6-10 days, more than 10 days) in the last 3 months. This information will be captured via patient report in REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Lost productivity (Caregiver Missed Work)
Patient Reported Survey: Number of days the patient's caregiver(s) (for patients \<18 years old at time of consent) missed work due to kidney stones or kidney stone-related care (0 days, 1-2 days, 3-5 days, 6-10 days, more than 10 days) in the last 3 months. This information will be captured via patient report on REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Lost productivity (Patient Missed Work)
Patient Reported Survey: Number of days the patient missed work (for patients 18 years and older at time of consent) due to kidney stones or kidney stone-related care (0 days, 1-2 days, 3-5 days, 6-10 days, More than 10 days) in the last 3 months. This information will be captured via patient report in REDCap.
Time frame: Every 3 months (+/- 14 days) from date of consent (observational cohort) or randomization (randomized cohort) until 24 months.
Plan to share: Undecided
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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