The phrase "a first onset of" is correct and usable in written English.
It can be used when describing the initial occurrence or beginning of a condition, event, or phenomenon.
Example: "The patient experienced a first onset of symptoms that indicated a possible allergic reaction."
Alternatives: "an initial occurrence of" or "the first appearance of".
The first group included 71 (45.5%) patients with a first onset of rheumatic fever (ARF), the second group 86 (54.5%) patients with a recurrent rheumatic fever (RHD).
The key difference between a 'prodrome' and 'risk syndrome' is that the former is primarily a predictor of the onset of an episode of the mental disorder under examination, whilst the latter is primarily a predictor of the overall likelihood that someone will experience a first onset of a disorder (compared to no disorder or another disorder).
An early detection programme aimed at staff in non-health service community organisations was well-implemented but ineffective in reducing duration of untreated psychosis or improving pathways to care for people experiencing a first onset of psychosis.
In combination with the rarity of the syndrome and thus the likeliness to become confronted with a first onset of the syndrome unprepared clearly makes it a challenge even for experienced anaesthesiologists [ 12].
In general, the probability of a first onset of depressive disorder after childhood adversities tended to decrease over time (mean reduction in effect 56%%), while no such time-dependent decrease was found for anxiety disorders.
North American research has found that non-health professionals are commonly involved in pathways to care for people with a first onset of psychosis [ 21] and that pathways involving non-medical professionals were associated with longer DUP [ 22].
In example (a), the first onset of the rupture of the small patches is delayed, but it propagates very rapidly once it has started.
An older minimal age of controls was used to reduce the chances that they might have a subsequent first onset of MD.
Serum hormone levels were examined in 34 men admitted consecutively for an acute exacerbation or first onset of schizophrenia in a blinded prospective design.
During the same time-span a significant shift in first onset of AIDS-defining illnesses was observed.
In these models, the independent variable is the age of onset of service use (any, and by type of provider) and the outcome variables are a) the age of first onset of suicide ideation (in the total population) and b) among those with a suicide ideation the age of first onset of a suicide plan and a suicide attempt.
