Disease Subheadings

Disease subheadings are filters or qualifiers that restrict records about a drug typed in the Disease name box to very specific aspects, such as drug resistance, epidemiology, therapy, etc. They are applied to diseases, disorders, syndromes, abnormalities, injuries and other pathologic conditions, and enable you to achieve a high degree of precision on these topics.

Except where otherwise noted, drug subheadings are available from 1988 onward.

You can search for subheadings alone or in combination. To select multiple subheadings, press the Windows Control key (or Mac Command key) and select the ones you want. When more than one are chosen, they are combined in an OR relationship by default; if you wish, you can change by clicking the AND button on the subheading list.

To search for subheading concepts prior to 1988, spell the term in full and combine it with a disease with a Boolean AND operator:

‘arm fracture’ AND surgery/de

Command-line search

You can add subheading codes manually to a query using command-line syntax.

leukemia/dm_dt: single subheading

leukemia/dm_dt,dd_th: multiple subheadings with OR

(leukemia/dm_dt AND leukemia/dm_rt): multiple subheadings with AND

‘leukocyte disorder’/exp/dm_dt,dm_rt: tree explosion with multiple subheadings (OR)

(‘leukocyte disorder’/exp/dm_dt AND leukocyte disorder'/exp/dm_rt): tree explosion with multiple subheadings (AND)

leukocyte/exp/dm_rt/mj: tree explosion with subheading and major focus

Subheadings can also be searched alone as "free-floating"? subheadings; e.g., not attached to a specific index term, with lnk.

‘prevention’/lnk

‘side effect’/lnk and [2009]/py

Disease Subheading

Code

Definition

complication

dm_co

Used for disorders or symptoms which arise as complications of pre-existing diseases or of medical procedures (with the exception of drug-induced complications, for which the subheading side effect is used). Note that the pre-existing disease is not linked to complication.

Congenital disorder

dm_cn

Used when attention is drawn to the congenital nature of a disease or malformation, including hereditary disorders present at birth. Also indexed as congenital malformation before 1988.

Diagnosis

dm_di

Used for the diagnosis of disease or the application of diagnostic tests.

Disease management

dm_dm

Used to identify diseases for which information is provided on the evaluation of healthcare costs (not restricted to drug therapy), including treatment outcome and quality of life studies. See related drug subheading pharmacoeconomics. Introduced in 1997.

Drug resistance

dm_dr

Used to identify any disease for which resistance to drug treatment is a significant aspect. Differentiate from drug tolerance, which is separately indexed. Introduced in 1996.

Drug therapy

dm_dt

Used to identify diseases and other conditions treated with drugs; includes curative, palliative, symptomatic and prophylactic treatment. For prophylactic treatment, the subheading prevention is also used.

Epidemiology

dm_ep

Used for the epidemiology of a disease, including its morbidity and mortality.

Etiology

dm_et

Used for both etiology (the factors causing the disease) and pathogenesis (the pathological mechanisms occurring in the development of the disease).

Prevention

dm_pc

Used for disease prevention and control; includes prophylactic treatment with drugs or vaccines, for which the subheading drug therapy is also used. Also indexed as prophylaxis before 1988.

Radiotherapy

dm_rt

Used for the treatment of disease using radiotherapy.

Rehabilitation

dm_rh

Used for procedures designed to rehabilitate patients recovering from a specific disease. Excludes physiotherapy, for which the subheading therapy is used.

Side effect

dm_si

Used for conditions which arise as undesired effects of drugs used at therapeutic dose ranges in humans, including drug-induced disease.

Surgery

dm_su

Used for the application of surgical techniques in the treatment of disease.

Therapy

dm_th

Used for any kind of therapy except drug therapy, radiotherapy and surgery (see more specific subheadings).