Welcome to NGC. Skip directly to: Search Box, Navigation, Content.


NGC Classification Scheme

Overview

The National Guideline Clearinghouse™ (NGC) uses controlled vocabulary concepts to classify various guideline attributes contained in the NGC Complete Summary. This standard "classification scheme" is designed to facilitate searching and retrieving information from the NGC Web site. In addition, the classification scheme attempts to standardize key guideline attributes to facilitate review of the guidelines, as well as comparisons between guidelines, particularly in the areas of methodology.

NGC classifies the following attributes:

New vocabulary concepts are added to the classification scheme as needed.

Clinical Specialty

The following concepts are used to classify the clinical specialties that might use the guideline professionally:

Return to Top

Disease/Condition

NGC uses Medical Subject Headings (MeSH) produced by the U.S. National Library of Medicine (NLM), along with other controlled vocabularies, such as the International Classification of Diseases (ICD), incorporated into NLM's Unified Medical Language System (UMLS) to classify disease concepts related to NGC guidelines.

Return to Top

Guideline Category

The following concepts are used to classify the major focus of each guideline:

Return to Top

Implementation Tools

The following concepts are used to identify tools used in the implementation of the guideline:

Return to Top

Institute of Medicine (IOM) Care Need

The following concepts are used to classify the IOM Care Need categories that apply to the guideline's primary clinical component:

Return to Top

IOM Domain

The following concepts are used to classify the IOM Domain categories that apply to the guideline's primary clinical component:

Return to Top

Intended Users

The following concepts are used to classify the intended users of each guideline:

Return to Top

Method of Guideline Validation

The following concepts are used to summarize the methods used to review or validate the recommendations of the guideline. Validation is defined as "the results of any external review, comparison with guidelines from other groups or clinical testing of guideline use" (Hayward RS, Wilson MC, Tunis SR, et al. More informative abstracts of articles describing clinical practice guidelines, Ann Intern Med 1993 May 1;118[9]:731-7).

Return to Top

Methods Used to Analyze the Evidence

The following concepts are used to classify the methods used by the guideline developer(s) to evaluate the data in the evidence they obtained:

Return to Top

Methods Used to Assess the Quality and Strength of the Evidence

The following concepts are used to classify methods used by the guideline developer to determine what relative importance to give to the evidence they obtained.

Return to Top

Methods Used to Collect/Select the Evidence

The following concepts are used to classify methods used by the guideline developers to collect the evidence that was evaluated:

Return to Top

Methods Used to Formulate the Recommendations

The following concepts are used to classify methods used by the guideline developers to formulate the guideline recommendations:

Return to Top

Organization Type

The following concepts are used to classify the guideline developer(s), guideline endorser(s), and issuing organization(s) by major designation or function:

Return to Top

Target Population

For the purposes of searching, NGC classifies the target population by age and sex. The following concepts are used:

Return to Top

Treatment/Intervention

NGC uses Medical Subject Headings (MeSH) produced by the U.S. National Library of Medicine (NLM), along with other controlled vocabularies, such as the U.S. Health Care Financing Administration (HCFA) Common Procedure Coding System and ECRI's Universal Medical Device Nomenclature System (UMDNS), incorporated into NLM's Unified Medical Language System (UMLS) to classify treatment/intervention concepts related to NGC guidelines.

Return to Top