In the 1998-1999 NHIS public use sample Codebooks, the NCHS defined the HINOTCOVE population as "persons who did not report having health care coverage at the time of the interview under private health insurance (from employer or workplace, purchased directly, or through a State, local government or community program), Medicare, Medicaid, public assistance, a State-sponsored health plan, other government programs, or military health plan (includes VA, CHAMPUS, TRICARE, and CHAMP-VA). Private plans that provide only extra cash while hospitalized or pay for only one type service such as nursing home care, accidents or dental care are not considered as coverage. Persons with only Indian Health Service coverage are considered uninsured."

In the 2000-2018 NHIS public use Codebooks, the NCHS defined the HINOTCOVE population as "persons who did not report having health care coverage at the time of the interview under private health insurance (from employer or workplace, purchased directly, or through a State, local government or community program), Medicare, Medicaid, Children's Health Insurance Program, a State-sponsored health plan, other government programs, or military health plan (includes VA, CHAMPUS, TRICARE, and CHAMP-VA)." As noted in the 2000-forward Field Representative's Manual, private health insurance excludes single service plans (i.e., plans that provide "for only one type of service," such as dental care, vision care, prescriptions, or cancer treatment). As in 1998-1999, "private plans that only provide extra cash while hospitalized" were not classified as constituting coverage, and persons with Indian Health Service coverage only were considered uninsured.

The 2019 NHIS public use Field Representative's Manual states, "An individual is considered currently insured if they currently have coverage through private health insurance, Medicare, Medicaid, Children’s Health Insurance Program (CHIP), military (TRICARE, Veterans Administration (VA), and CHAMP-VA), other state-sponsored health plans, or other government program. Individuals without any of the aforementioned coverages or with only Indian Health Service coverage or a non-comprehensive plan that covers only dental, vision, or prescription drugs are considered uninsured."

A code of "yes" in the following bulleted recoded variables means that the person is insured, and thus is not uninsured:

• HICHIPE (Covered by Children's Health Insurance Program: Recode, 1999-2003)

• HIPRIVATEE (Covered by private health insurance: Recode)

• HIMILITE (Covered by military health insurance: Recode)

• HIMCAREE (Covered by Medicare: Recode)

• HIMCAIDE (Covered by Medicaid: Recode)

• HISTATEE (Covered by other state-sponsored health plan: Recode)

• HIOTHGOVE (Covered by other government program: Recode)

According to the standard set by NCHS, a code of "no" in all of the bulleted variables listed above means that the person is "HINOTCOVE." The uninsured population also encompasses persons who had a code of "yes" in HIHSE (Covered by Indian Health Service: Recode) but not in any of the variables bulleted above.

This definition, whether stated in text form (as in the first two paragraphs of this document), or in terms of reference to specific variables (as is the case directly above), follows the standard set in the NCHS publication Health, United States.