WONCA International Classification Committee

IATROGENIC DISEASE

A health problem caused by a physi-cian's diag-nostic or therapeutic activities.

ICD

See INTERNATIONAL CLASSIFICATION OF DISEASE.

ICEBERG PHENOMENON

Refers to the situation where only a part of the health problems is detected, specifically because of people not seen by health care providers, and because patients deliberately do not present all their health concerns when attending. The "visible" part is the detected health problems, and the "submerged" part is health problems not yet diagnosed or medically attended to.

ICPC

See INTERNATIONAL CLASSIFICATION OF PRIMARY CARE.

INCEPTION COHORT

A designated group of persons, assembled at a common time early in the development of a specific health problem (eg at the time of first exposure to the putative cause or at the time of initial diagnosis), who are followed thereafter.

IDENTIFICATION NUMBER

Different countries have developed different codes by which they can identify each individual. They often consist of digits from date of birth, gender etc.

ILLNESS

The sub-jective state of the per-son, who is aware of having a health problem and not feeling well.

ILLNESS BEHAVIOUR

The conduct of a person in response to ab-no-rmal mental and physical signals. Such behaviour influences the manner in which a person monitors, defines, and interprets bodily symp-toms, takes remedial actions, and uses the health care system.

ILLNESS DIVERSITY

The number of different episodes experienced by a patient in a year.

IMRAD

Abbreviation of the sections of a scientific publication : Introduction, Methods, Results, Analysis and Discus-sion.

IMPAIRMENT

Any reduction or abnormality of psychologic-al, physiolo-gical, or anatomical structure or function.

INCIDENCE

The number of new instances of illness or of persons falling ill, during a given period in a specified population (usually per 1,000 population per year).

INDEPENDENT VARIABLE

See VARIABLE.

IN-DEPTH INTERVIEW

An interview method used in qualitative research which aims at understanding the experience from the informant, interpreted by the interviewer. Repeated encounters often help the interviewer (ie the researcher) to understand the informant's perspective on his/her situation and life, as expressed by him-/herself.

INDEX

An aggregation of two or more distinct health measures into an overall summary measure. In functional status assessment, index means a rating scale derived from a number of measurements on different func-tional assessment scales which have no internal relationship.

INDEX CONDITIONS

Selected health problems or diagnosis chosen for measurement in an audit or research programme as indicators of the overall quality of care.

INDICATORS

Particular elements of care selected for assessment in performance review, and between which a hierarchy and internal relationship exist.

INDUSTRIAL PRACTICE

A practice conducted within the confines of an industrial organisation. Usually the physician is reimbursed by salary, or according to terms of a specific contract. Ancillary staff are usually employees of the industry.

INFANT

A child less than one year of age.
1. Neonate - birth to 28 days.
2. Post-neonate - 29 days to 1 year.

INFANT MORTALITY RATE

The number of infant deaths in a year divided by the total number of live births in that year and stated as number per 1,000. This rate is used as an indicator of the health standard of a society.

INFECTION

The entry and multiplication of an infectious agent in a person, this may or may not give rise to symptoms or disease. A person carrying an infectious agent without being ill is called a "carrier" of that agent or health problem.

INFERENCE

Conclusions drawn on evidence from clinical research by the professional community, readers of literature, or even by the investigator who presents the empirical evidence. INFERENCE implies judgement on basis of evidence and prior belief. INFERENCE prior belief in posterior belief, given the scien-tific evidence.
Statistical inference is the development of generalization from sampled data to a virtually larger population than sampled, usually with calculated degrees of uncertainty around the calculated outcome measure.

INFESTATION

Usually applied to parasites as causative agents eg infested with lice.

INFORMED CONSENT

Consent given by a person who is invited to participate in a research project or a teaching session after being well informed of the aims, consequences, burden, time, risk etc. He/she must be offered the option of not participating, if so desired, without detriment to the care being received.

INPATIENT

A patient who is admitted to and spends at least one night in hospital.

INSTITUTIONAL VISIT

A professional attendance to two or more patients in one institution on the same occasion.

INTERACTIVE

Acting upon each other, in the context of education interactive teaching is learning situations in which partici-pants teach and learn at the same time.

INTER-DOCTOR VARIATION

Variation between providers in frequencies of health problems, that cannot be explained by the age-sex distribution of their practices. INTER-DOCTOR VARIATION can be observed on reasons for encounters, diagnoses and inter-ventions. INTER-DOCTOR VARIATION is related to small area variation, which concerns more aggregated data on group-practices, hospitals or regions.

INTERNATIONAL CLASSIFICATION OF DISEASE (ICD)

An international classification developed under the auspices of WHO and published periodically as a complete book on diagnostic entities. It is organi-sed in 17 chapters con-taining more than 12,000 different catego-ries. Each entry is given a numerical code of up to four digits. This publica-tion is called : "Manual of the Inter-national Statistical Classification of Diseases, Injuries and Causes of Death". The Tenth Revi-sion (ICD-10) was introduced on January 1, 1993, but is so far only implemented in very few countries. It replaces ICD-9 published in 1976.

INTERNATIONAL CLASSIFICATION OF HEALTH PROBLEMS IN PRIMARY CARE

The classification of diseases and conditions in primary care. First produced by the WONCA CLASSIFICATION COMMITTEE, and it has been revised once under the name ICHPPC-2. Ii is now replaced by the much more prac-tice orientated ICPC. ICHPPC is structured in the same way as the ICD-9 clas-sification.

INTERNATIONAL CLASSIFICATION OF IMPAIRMENTS, DISABILITIES, AND HANDICAPS

Published by WHO in 1980 as a taxonomy of the consequences of injury and disease. It uses the fol-lowing defini-tions :
1. Impairment : "Any loss or abnormality of psychological, physio-logical or anatomical structure or function". Im-pairments represent disturbances at the organ level.
2. Disability : "Any restriction or lack (resulting from an impairment) of ability to perform an ac-tivity in a manner or within the range considered normal for a human being". Disability repre-sents disturbances at the level of the person.
3. Handicap : "A disadvantage for a given individual, resul-ting from an impairment or a disability, that limits or prevents the fulfilment of a role that is normal (depending on age, sex, and social and cultural factors) for that individual". It re-flects the adaptation of the individual to his/her surroundings.

INTERNATIONAL CLASSIFICATION OF PRIMARY CARE

The classification which takes best into account the way the GP/FP works. In this classification the reason for the encounter (REF) can be classified as well as the diagnostic processes, intervention, prevention, administrative procedures and the diag-nosis. It has a biaxial structure and is built up in 17 chapters, each divided up in 7 com-ponents. It has been extensively tested and found to be very practicable and reliable for use in general prac-tice, with less than 3% recor-ding error. It was published by the WONCA Classification Committee in 1980 and a new version with definitions and correc-tions is planned.

INTERPOLATE

To predict a value within the range of observed values.

INTERVAL SCALE

A scale in which the distances between all levels along the scale have known numeric values and with no zero level.

ITEM

A single question or statement and its standardized response scale.

JOB DESCRIPTION OF A GENERAL PRACTITIONER/FAMILY PHYSICIAN

The general practitioner is a licensed medical graduate who gives personal, primary and continuing care to individuals, families and a practice population, irrespective of age, sex and illness. It is the synthesis of these functions which is unique. He will attend his patients in his consulting room and in their homes and sometimes in a clinic or a hospital. His aim is to make early diagnoses. He will include and integrate physical, psychological and social factors in his considera-tions about health and illness. This will be expressed in the care of his patients. He will make an initial decision about every problem which is presented to him as a doc-tor. He will undertake continuing management of his patients with chronic, recurrent or terminal illnesses. Prolonged contact means that he can use repeated oppor-tunities to gather infor-mation at a pace appropriate to each patient and build up a relationship of trust which he can use professionally. He will practice in co-operation with other colleagues, medical and non-medical. He will know how and when to intervene through treat-ment, prevention and education to promote the health of his patients and their families. He will recognise that he also has a professional responsibility to the community. (Leeuwenhorst 1974).

LIFE EVENTS

Changes or disruption of life caused by socio- economic changes or other external factors, which have an effect on health. They can be positive or negative for the in-dividual. Rating scales have been constructed to try and measure this effect on people's life.

LIFE-STYLE

The way each individual lives with respect to eating, working, smoking, drinking, socialising, exercise and other habits which have a profound effect on the person's health and well-being. One of the important tasks of the family physician is to help patients to awareness of life-style induced symptoms or diseases.

LIKERT SCALE

A scale evaluated and scored according to the method of summated ratings in which items are summed or averaged to obtain an overall score.

LINKAGE

In a classification system, the linkage is the manner in which parts of separate classifications can be united

LITERATURE SEARCH

A systematical search for literature on a specified subject of interest. One can perform a LITERATURE SEARCH by hand with help of a library and referen-ces of retrieved publications, or by computer with help of a retrieval system which can search in data banks of the medical literature, eg Medline or Embase.

LOCUM TENENS

A practitioner employed for a stated period of time by a physician to assume responsibility for the care of his/her prac-tice population during his/her absence. Respon-sibility reverts to the principal physician upon his return.

LONGITUDINAL STUDY

See COHORT STUDY.