Section 7

Sources and caveats

Everything here traces to a primary source where one exists. Where a figure is an estimate or a source is uncertain, it says so.

Denial and appeal data

• KFF — Medicare Advantage insurers made nearly 53 million prior authorization determinations in 2024. Source for the 52.8 million figure, the 7.7% denial rate, the 11.5% appeal rate, and UnitedHealth's 12.8% denial rate — the highest among major insurers examined.
• KFF — Prior authorization metrics provide new insights into insurer practices (August 2026). The first year of publicly reported data under the new federal rule.
• KFF — post-acute care denial rates
• KFF — Medicare Advantage in 2026. Source for the finding that 95% of enrollees are in plans requiring prior authorization for skilled nursing and 90% for home health.

Federal Inspector General reports

• HHS OIG (June 2026) — 95% of appealed skilled nursing denials overturned. Also the source for the finding that naviHealth, a UnitedHealth subsidiary, processes half of all skilled nursing requests nationally and had a 97% overturn rate.
• HHS OIG (June 2026) — long-term acute care and inpatient rehabilitation denial rates
• HHS OIG (2022) — 13% of MA prior authorization denials would have been covered under Original Medicare, naming post-acute facility stays as a top category.
• U.S. Senate Permanent Subcommittee on Investigations (October 2024) — documents UnitedHealthcare's post-acute denial rate rising from 8.7% in 2019 to 22.7% in 2022, and home health prior authorization requests rising 18-fold.

Physical therapy and the Jimmo standard

• CMS — Therapy Services, and APTA — payment thresholds. Source for the 2026 KX threshold of $2,480 and targeted review threshold of $3,000, and for the fact that no prior authorization exists for outpatient PT under Original Medicare.
• APTA — Impact of Administrative Burden on Physical Therapy Services (November 2025). Source for the finding that 83% of physical therapists report prior authorization causing patients to abandon treatment.
• CMS Jimmo Settlement Center and the CMS Jimmo Fact Sheet — the court-ordered corrective statement holding that coverage turns on the need for skilled care, not on improvement.
• Center for Medicare Advocacy — Jimmo FAQs, confirming that the standard binds Medicare Advantage plans. Free tools: the Jimmo appeal letter template and the self-help packet for outpatient therapy denials.

Regulations cited

• 42 CFR 422.101 — Medicare Advantage plans must follow Medicare coverage rules; subsection (b)(6) limits internal criteria to areas where Medicare criteria are not fully established.
• 42 CFR 422.138 — a prior authorization approval must remain valid as long as medically reasonable and necessary.
• 42 CFR 422.136 — step therapy for office-administered drugs limited to new administrations with at least a 365-day lookback.
• 42 CFR 422.568 — the 7-calendar-day standard decision requirement effective January 2026.
• CMS Interoperability and Prior Authorization Final Rule (CMS-0057-F) — 72-hour expedited and 7-day standard decisions, specific denial reasons required, public reporting of denial metrics.

Prescription drug rules

• CMS Prescription Drug Benefit Manual, Chapter 6 — §10.4 on compounded drugs and the rule that bulk active ingredients are not Part D drugs; §10.6 on what counts as a medically accepted indication and which compendia are recognized.
• CMS — Final CY2026 Part D Redesign Program Instructions. Source for the $2,100 out-of-pocket cap and $615 maximum deductible.
• Avalere Health — "Part D Formulary Management Tightens in 2026". The source for the finding that prior authorization on covered brand drugs increased in 2026 — up 3 percentage points for standalone Part D plans and 2 points for Medicare Advantage drug plans — and that prior authorization rates remain slightly higher for standalone plans than for MA-PD plans. This is the basis for the conclusion that switching to Original Medicare plus a standalone Part D plan would not fix the prescription denials.
• Medicare Plan Finder — for comparing formularies drug by drug.

Osteoporosis

• Tymlos (abaloparatide) FDA label — §1.2 contains the male indication added December 2022, with no "primary or hypogonadal" qualifier.
• Forteo (teriparatide) FDA label — note the narrower "primary or hypogonadal" male indication.
• Fuggle et al. — ESCEO/IOF evidence-based guideline for the management of osteoporosis in men, Nature Reviews Rheumatology (2024)
• Ramchand & Leder — Sequential Therapy for the Long-Term Treatment of Osteoporosis, JCEM (2024). States directly that prior antiresorptive use is not a contraindication to anabolic therapy.
• Lewiecki et al. — BRIDGE trial of romosozumab in men, JCEM (2018)
• CMS billing and coding article for denosumab — the covered diagnosis code list, relevant to the coding caution on the conditions page.

Ophthalmic coverage

• American Academy of Ophthalmology — billing autologous serum tears. States that most payers have no allowable for them.
• AAO EyeNet — Diagnosing and treating neurotrophic keratopathy
• CMS — Amniotic membrane, sutureless placement on the ocular surface. The basis for treating amniotic membrane as a Part B medical benefit rather than a pharmacy claim.
• UnitedHealthcare prior authorization criteria for Oxervate — note this is the commercial policy; the Medicare Part D version may differ and should be requested from the plan.

Texas-specific

• Texas Department of Insurance — Medicare supplement insurance guide. Note: this page still contains pre-2020 plan-letter language and should not be relied on for which plans are available.
• TDI — Getting help with a health plan that TDI doesn't regulate, confirming that Medicare Advantage is federally regulated and outside TDI's authority.
• Texas Insurance Code §1952.152 — PIP must be included unless rejected in writing.
• §1952.155 — PIP benefits paid regardless of fault and regardless of other coverage; generally no subrogation.
• §1952.156 — 30-day payment requirement and proof-of-loss window.
• SHIP TA Center — Texas and Texas Legal Services Center — HICAP

The Valero plan

• Valero Retiree Benefits — Medicare options, listing the UnitedHealthcare Group Medicare Advantage plan and the United American supplement tiers.
• Valero 2025 UnitedHealthcare Group Medicare Advantage Plan Guide — the source for the $0 out-of-pocket maximum, national service area, and equal out-of-network cost sharing.
• Valero Retiree Benefits Handbook, effective January 1, 2024 — contains the language about waiving rights to benefits.

The WISeR pilot

• CMS — WISeR Model and KFF — Examining the potential impact of Medicare's new WISeR model. Began January 1, 2026 in Arizona, New Jersey, Ohio, Oklahoma, Texas, and Washington; runs through 2031. The covered service list has shifted since launch — CMS withdrew the skin substitute determinations in December 2025 and delayed two other services in April 2026 — so any specific count should be treated as approximate.

Caveats worth reading