Prior authorization — check member benefits

Verify member benefits and any applicable prior authorization rules before ordering diabetes-related laboratory testing; the policy does not specify procedure codes requiring prior authorization in this excerpt and coverage depends on the member's benefit coverage and applicable regulations.

• Check member-specific benefit documents and any state or Medicare/Medicaid requirements prior to testing.
• Procedure codes for reference include CPT 82947, 82951, 82952, 82985, 83036, 83037 but this policy lists them for reference only and may not indicate authorization requirements.

Prior authorization — none specified in policy text

This policy contains no explicit universal prior authorization requirement for the tests described; providers should nonetheless confirm payer-specific rules as coverage and reimbursement may vary.

Prior authorization — no prior auth statements

No statements in this section require prior authorization for diabetes testing; verify any site- or contract-specific authorization processes before ordering.

Prior authorization — none specified (clinical guidance only)

There are no policy-specified prior authorization requirements here; clinical recommendations (for example perioperative medication holds and monitoring) are provided but do not replace benefit verification.

Procedure code reference — verify coding and benefits

Use the listed CPT codes when coding diabetes-related laboratory tests and confirm that coding aligns with submitted documentation and member benefits.

• CPT 82947 — Glucose; quantitative, blood
• CPT 82951 — Glucose; tolerance test (GTT), 3 specimens
• CPT 82952 — Glucose; tolerance test, each additional beyond 3 specimens
• CPT 82985 — Glycated protein
• CPT 83036 — Hemoglobin; glycosylated (A1C)
• CPT 83037 — Hemoglobin; glycosylated (A1C) by device cleared by FDA for home use

Prior authorization — no requirements stated

No prior authorization requirements are indicated for the tests in this portion of the document; confirm any payer- or contract-level prior authorization expectations before testing.

Step therapy — none specified

The policy does not specify any step therapy requirements for laboratory testing in the provided sections; no pharmacologic step therapy rules are described here.

Provider actions — follow ordering and documentation guidance

Provider actions related to ordering and documenting diabetes testing are summarized throughout the policy; follow the specific documentation and method-certification requirements noted elsewhere in the policy when ordering tests.

Perioperative medication instructions and insulin adjustments

Follow perioperative medication instructions: hold metformin on the day of surgery and discontinue SGLT2 inhibitors 3–4 days before surgery; hold other oral glucose-lowering agents the morning of surgery and adjust insulin dosing (e.g., reduce basal insulin by ~25% the evening before) as clinically indicated.

• Hold metformin on day of surgery.
• Stop SGLT2 inhibitors 3–4 days before surgery.
• Hold other oral agents the morning of surgery; give half of NPH dose or 75–80% of long-acting analog insulin the evening before as appropriate.
• Monitor blood glucose at least every 2–4 hours while NPO and dose short- or rapid-acting insulin as needed.

Step therapy — no rules in this policy excerpt

No step therapy requirements are specified in these excerpts; continue to follow clinical guidance and benefit rules for medication management outside this policy.

Documentation requirements — code and medical necessity support

Submit accurate, complete documentation supporting the services performed and code claims according to industry-standard coding guidelines; payers may deny or recoup payment if coding/billing guidelines or reimbursement policies are not followed.

• Ensure documentation supports the medical necessity and applicable procedure and diagnosis coding.
• Follow Uniform Billing, AMA CPT guidance, CMS NCCI and other applicable coding rules.

Document A1C method certification and POC device status

Document the A1C assay method used and its certification: record that laboratory A1C methods are NGSP-certified and traceable to the DCCT reference assay; for point-of-care A1C, document the device is FDA-approved and testing occurred in a CLIA-certified laboratory with trained personnel.

• Record NGSP certification and DCCT traceability of the A1C method.
• For POC A1C, document FDA clearance of the device, CLIA certification of the lab, and evidence of trained personnel performing moderate-complexity testing.

Hospital / perioperative documentation — A1C and monitoring plans

For hospital and perioperative care, perform and document an A1C if no result is available from the prior 3 months; document perioperative A1C goals, planned glucose monitoring frequency, and medication-holding instructions.

• Obtain A1C if no result from prior 3 months on hospital admission.
• Document perioperative A1C goals (elective surgery goal <8% when possible) and perioperative blood glucose target (100–180 mg/dL).
• Document planned glucose monitoring frequency and instructions to hold metformin and SGLT2 inhibitors as specified.

Document HbA1c method and alternatives when A1c is invalid

Document the HbA1c assay calibration method (IFCC calibration recommended) and, when HbA1c is invalid due to abnormal erythrocyte turnover or hemoglobin variants, document the alternative monitoring approach used (quality-controlled plasma glucose profiles, total glycated hemoglobin, or fructosamine).

• Record IFCC-calibrated HbA1c method where applicable.
• If A1c is invalid, document which alternative test or monitoring method was used and the rationale.

GDM screening/diagnosis documentation — timing and approach

When screening or diagnosing gestational diabetes, document the timing (24–28 weeks for routine GDM screening), the diagnostic approach chosen (one-step 75-g 2-hour OGTT or two-step 50-g screen followed by 100-g OGTT), and the specific glucose cutoff values used for diagnosis.

• Document whether one-step (75-g 2-hour OGTT) or two-step (50-g screen ± 100-g OGTT) approach was used.
• Record exact glucose thresholds applied and gestational age at screening (24–28 weeks).

Guideline references — supportive citations only

This section of the policy provides guideline citations and references to support clinical decision-making but does not itself create additional documentation submission requirements for authorization.

Denial risk triggers — coding, billing, and unsupported wellness FPG

Claims may be denied or payment recouped if coding/billing guidelines or reimbursement policies are not followed; fasting plasma glucose testing at a wellness visit with no abnormal findings does not meet criteria and may be rejected.

• Order and code FPG/A1c/OGTT only when medical necessity is documented per policy criteria.
• Avoid routine wellness FPG testing without abnormal findings as it does not meet criteria.

Denial risk — non‑NGSP or non‑FDA/CLIA POC A1C methods

Using A1C methods that are not NGSP-certified, or point-of-care A1C devices that are not FDA-approved and performed in CLIA-certified labs by trained personnel, may result in noncompliant testing and potential denial of coverage for diagnostic use.

• Confirm NGSP certification and DCCT traceability for laboratory A1C.
• For POC A1C, document FDA clearance and CLIA-certified lab testing performed by trained staff.

Certified A1C methods required for diagnostic/monitoring use

The policy requires use of NGSP-certified/DCCT-traceable A1C methods for diagnosis or monitoring; point-of-care A1C must be FDA-approved and performed in CLIA-certified laboratories — failure to use certified/approved methods can render results invalid for diagnostic or coverage purposes.

• NGSP certification and DCCT traceability are required for A1C testing.
• POC A1C testing must be restricted to FDA-approved devices in CLIA-certified labs with trained personnel.

Denial risk — incomplete perioperative glucose monitoring documentation

Failure to document perioperative blood glucose monitoring at least every 2–4 hours while the patient is NPO, and to dose short- or rapid-acting insulin as needed, may risk noncompliance with hospital care delivery standards.

• Document monitoring frequency (at least every 2–4 hours while NPO) and insulin dosing decisions.
• Record rationale if monitoring frequency or insulin dosing deviates from recommended practice.

Denial risk — GDM timing and diagnostic approach

Failure to perform GDM screening at the recommended timing (24–28 weeks) or to use an accepted one-step or two-step diagnostic approach may lead to nonconcordant care decisions and impact coverage or quality reporting.

• Screen for GDM universally at 24–28 weeks unless earlier screening for undiagnosed diabetes is indicated.
• Document which diagnostic algorithm and thresholds were used.

Policy publication and denial rules

There are no additional denial rules specified in this section; publication history documents original governance approval on 06/16/2026.