Category: N

Distortion introduced into a research investigation by incomplete collection of data from all possible respondents. This bias is most likely to influence the results of a study when those who do not participate or who refuse to be sampled have other crucial characteristics that the study is designed to identify.  

An individual who does not achieve an immunological response to a vaccine.  

The name of a drug other than its trademarked (proprietary) name. The nonproprietary name for a new drug is usually the same as that selected by the United States Adopted Name (USAN) Council. The official names for older drugs may differ from the nonproprietary names. In some cases the generic name is the same as…

An individual infected with the human immunodeficiency virus who does not develop worsening immune function or symptoms of active disease.  

In alcohol-related research, alcohol consumption that does not adversely affect a person’s physical or mental health, or his or her occupation, family life, or functioning in society. The consumption of less than one standard drink daily normally constitutes nonproblematic drinking.  

Not having separate poles; sharing electrons.  

Not detectable during manual examination but identified instead with radiological or other diagnostic means.  

A general class of surface-active agents with the basic formula of C15H240(C2H40)n, named with respect to the value of n. Nonoxynol 9 is a spermicide.  

A type of malocclusion in which the teeth fail to make contact.  

The principle of not doing something that causes harm. Hippocrates felt this was the underpinning of all medical practice. He advised his students, primum non nocere (“first, do no harm”).