Table 7

Studies providing indirect adverse event classification system only (n = 10).

Authors, year, citationStudy designClassification system
Barrett et al. 2000 []SurveyHardly any discomfort, mild discomfort, moderate discomfort, severe discomfort, worst possible discomfort—one hour, one day and two days after SMT’’
Meeker et al. 2002 []Review“. . . onset within 4 hours of the procedure, disappearing within 24 hours’’; ’’Serious complication cases including fatalities, major impairments’’
Mentions severe, serious
Anderson-Peacock et al. 2005 []Clinical Practice GuidelineNon-treatment adverse events–not associated with a treatment modality, but that occur in the clinical setting;
Unforseen-treatment adverse events–associated with a treatment modality, but not a known or observable risk factor;
Forseen-treatment adverse events–associated with a treatment modality and predicted by an observable risk factor
Cleland et al. 2007 []Trial“Subjects. . . were asked to report the time of onset (categorized as ≤24 hours or >24 hours), the duration (categorized as ≤24 hours or >24 hours), and the severity (scored on a scale of 1–4, where 1 = light to 4 = severe) of the symptoms’’; Mentions mild, moderate, serious
Dagenais et al. 2010 []ReviewMinor, temporary, self-limiting (side-effects)
serious; last between several hours and a few days
Carlesso et al. 2010 []Review“The adverse events were initially grouped into major—death, stroke or permanent neurological deficits and minor—transient neurological symptoms, increased neck pain/stiffness, headache, radiating pain, fatigue or other’’
Yin et al. 2014 []ReviewMild, minor, moderate, medium, serious; appeared within 4–24 hours of treatment; disappeared within 24 hours; rated ≤ NRS regarding severity
Coulter et al. 2019 []ReviewMinor; typically transient
Funabashi et al. 2020 []SurveyVariation in terms of frequency and severity, ranging from the more frequent minor/benign adverse events to rare and serious adverse events
Zhang et al. 2021 []Protocol“Shedding criteria: 1) intolerable adverse reactions; 2) serious adverse reactions; 3) the patients’ pain continued to increase, which proved that trial participation was not suitable; 4) the patient’s health may be damaged (for example, serious complications)’’

NRS: numeric rating scale;
SMT = spinal manipulative therapy.