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From: Ian A. York
Subject: Re: Full Moon and Human Behavior
Date: Sep 20 1996

In article  <51i66l$> (Ron)

>       I'm a physician, and have for years thought I'd like to do
>controlled research on the effects of full moon on human behavior.
>Folklore has it that wolves and dogs howl, cats prowl, humans become more
>romantic, the elderly become more confused and have more accidents and
>injuries, and the mentally ill become more agitated.  However, I'm unaware
>of any objective research in this area.  Is anyone aware of any research
>articles or publications which address this issue?

There is a fair bit of literature on this; Medline lists quite a few
articles.  The conclusion is there is no such effect. I looked into this
a bit a while back on the newsgroup alt.folklore.urban; here
is the post I made then:

In article <4bri30$>,
Rob Carscadden  <> wrote:
>I'm sure that more accidents happen during a full moon is an UL. It justs 
>sticks in peoples mind more when the ER is full on a full moon. I've seen 
>the data that debunks this UL but I can't recall where. 

This is certainly a widely believed phenomenon, even (especially) among 
medical types [1], but it's simply not true.  Large-scale studies have 
found no association between the phase of the moon and childbirth [2-3], 
suicide [4-7] (one study did find a very small difference, with women 
only, showing fewer attempts at full moon; other larger studies found no 
such effect), accidents [8] (again, a very small effect - this time of 
crescent moon - was seen, but was probably a small-sample effect), crisis 
calls [9], and absenteeism [10].

Why do people believe this?  It's probably the heads-I-win, 
tails-doesn't-count approach.  If you're in the emergency room, and it's 
a busy night, it's just a busy night.  If it's a busy night and there's a 
full moon, then it's the moon effect.  If it's quiet - well, that doesn't 
count.  Humans are pattern-seeking animals.  

It's worth mentioning that there are people who firmly believe in the
lunar effect, such as J. Sitar, member of the esteemed institution
"Interni ambulance polikliniky Kurim Okresniho ustavu narodniho zdravi
Brno-venkov"  (and a spiritual member of the Abianian school of thought). 
Sitar has published a number of articles on this effect, a representative
example of which is [11]. 


[1]  Vance DE.
  Belief in lunar effects on human behavior.
  Psychological Reports.  76(1):32-4, 1995
  Questionnaires sent to 325 people indicated that 140 people (43%) held the
  personal belief that lunar phenomena alter individual behavior.
  Specifically, mental health professionals (social workers, master's
  clinical psychologists, nurses' aides, LPNs) held this belief more
  strongly than other occupational groups.

[2]  Periti E.  Biagiotti R.
  [Lunar phases and incidence of spontaneous deliveries. Our experience].
  Original Title: Fasi lunari ed incidenza di parti spontanei. Nostra
  Minerva Ginecologica.  46(7-8):429-33, 1994
  OBJECTIVE. To evaluate the relationship between lunar phases and
  birthrate. STUDY DESIGN. We examined 7842 spontaneous deliveries at
  Obstetric and Gynaecologic Clinic of University of Florence, between
  [ ... ] 
  CONCLUSIONS. These results do not support the hypothesis of a relationship
  between moon-phase changes and the incidence of spontaneous deliveries.

[3]  Strolego F.  Gigli C.  Bugalho A.
  [The influence of lunar phases on the frequency of deliveries]. 
  Original Title:  Influenza delle fasi lunari sulla frequenza dei parti.
  Minerva Ginecologica.  43(7-8):359-63, 1991
  [ ... ] 
  anticipating it. To verify the veracity of this belief, we studied the
  frequency of home deliveries of Maputo (Mozambique), without any medical
  assistance according to lunar cycle. A study of 5226 births in 37 lunar
  cycles didn't show a significative increase of deliveries during specific
  lunar phases and week days. The same result has been achieved expanding
  the examination period to 2 days before and after lunar phase. Therefore,
  on the basis of this study, the hypothesis that lunar phase may influence
  the process of birth is disproved.

[4]  Buckley NA.  Whyte IM.  Dawson AH.
  There are days ... and moons. Self-poisoning is not lunacy.
  Medical Journal of Australia.  159(11-12):786-9, 1993
  [ ... ] 
  were 2215 patients admitted. There was a marked circadian variation. Over
  6% of all admissions occurred in each of the hours between 6 p.m. and 1
  a.m. compared with less than 2% per hour between 5 a.m. and 9 a.m. This
  pattern was not different for patients with a diagnosis of depression.
  Numerology, biorhythms and star signs had no significant correlations with
  self-poisoning, nor was there a significant weekly or yearly variation in
  presentations. There was a small but statistically significant sex
  difference in presentations analysed by lunar phases. At the new moon 60%
  of self-poisonings were in women, compared with 45% when the moon was
  full. The odds ratios (OR) for women to be admitted at full moon and at
  new moon were 1.27 (95% confidence interval [CI], 0.92-1.66; P value not
  significant) and 0.73 (95% CI, 0.57-0.92; P = 0.009) respectively. The
  mean illumination of the moon at the time of overdose was 50.63% +/- 0.91%
  for men, compared with 47.45% +/- 0.85% for women (P = 0.014). CONCLUSION:
  The circadian cycle (but not weekly, yearly or mystical cycles) should be
  taken into account when determining staffing levels for poison information
  and casualty services. The full moon is protective for women.

[5]  Martin SJ.  Kelly IW.  Saklofske DH.
  Suicide and lunar cycles: a critical review over 28 years. 
  Psychological Reports.  71(3 Pt 1):787-95, 1992 Dec.
  20 studies which have examined the relations between completed suicide or
  attempted suicide and suicide threats with the synodic lunar cycle are
  reviewed. Most studies indicated no relation between lunar phase and the
  measures of suicide. The positive findings conflicted, have not been
  replicated, or were confounded with variables such as season, weekday,
  weather, or holidays. It is concluded that there is insufficient evidence
  for assuming a relationship between the synodic lunar cycle and completed
  or attempted suicide.

[6]  Maldonado G.  Kraus JF.
  Variation in suicide occurrence by time of day, day of the week, month,
  and lunar phase.
  Suicide & Life-Threatening Behavior.  21(2):174-87, 1991 Summer.
  [ ... ]
  cases. 4,190 suicide deaths were identified during the study period.
  Suicide occurrence varied substantially by time of day; for both sexes and
  for ages under 65 years, the fewest suicide deaths occurred during the
  early morning hours, from 0401 to 0800. For recent years of the study,
  suicides occurred most frequently on Monday for both males and females and
  for most age groups. Variation by month followed no consistent pattern by
  gender, age, years of the study, or combinations of these factors.
  Contrary to popular belief, suicide occurrence did not vary by lunar

[7]  Rogers TD.  Masterton G.  McGuire R.
  Parasuicide and the lunar cycle.
  Psychological Medicine.  21(2):393-7, 1991 May.
  Admissions to hospital following parasuicide in one city over eighteen
  years exhibit a cyclical variation apparently synchronized with the lunar
  quarters. The effect would only account for approximately 0.7 out of the
  average of 46 parasuicides per 100,000 adults per lunar cycle (95% CI
  0.6-0.8), and fails to reach statistical significance.

[8]  Alonso Y.
  Geophysical variables and behavior: LXXII. Barometric pressure, lunar
  cycle, and traffic accidents.
  Perceptual & Motor Skills.  77(2):371-6, 1993 Oct.
  This study assessed relationships between traffic accidents and variables
  [ ... ] 
  days before the full moon. Accidents occurred more frequently during
  crescent moon than during waning moon, but no significant differences were
  noted when the lunar month was divided into four intervals of new moon,
  first quarter, full moon, and second quarter.

[9]  Byrnes G.  Kelly IW.
  Crisis calls and lunar cycles: a twenty-year review.
  Psychological Reports.  71(3 Pt 1):779-85, 1992 Dec.
  12 studies are reviewed that have examined the relationships among crisis
  calls to police stations, poison centers, and crisis intervention centers
  and the synodic lunar cycle. On the basis of the studies considered it is
  concluded that no good foundation exists for the belief that lunar phase
  is related to the frequency of crisis calls. In addition, there is no
  evidence whatsoever for the contention that calls of a more emotional or
  "out-of-control" nature occur more often at the full moon. 

[10]  Sands JM.  Miller LE.
  Effects of moon phase and other temporal variables on absenteeism.
  Psychological Reports.  69(3 Pt 1):959-62, 1991 Dec.
  Previous research on the effects of lunar phase on deviant behavior has
  produced weak and inconsistent results and has been criticized for failing
  to use appropriate statistical controls. This study examined the effects
  of the full moon on daily absenteeism rates in a large organization while
  correcting for autocorrelation and controlling for the effects of the day
  of the week, month, and proximity to a holiday. Contrary to expectations,
  the full moon was associated with a significant (but very slight) decrease
  in absenteeism. Reasons for persistent beliefs in the effects of the full
  moon are discussed.

[11]  Sitar J.
  [The causality of lunar changes on cardiovascular mortality]. [Czech]
  Original Title:  K pricinam lunarnich zmen kardiovaskularni umrtnosti.
  Casopis Lekaru Ceskych.  129(45):1425-30, 1990 Nov 9.
  The author confirmed, based on different ways of processing of 1437 sudden
  cardiovascular deaths, that the frequency of these deaths changes in the
  course of the synodic moon with two maxima during the lunar quarters.
  Processing by the method of transfer of epochs made it possible to shift
  steadily the mortality curves according to the phase of solar activity.
  This made the author assume that the cause of the phenomenon of two-phasic
  change of mortality during lunation cannot be only gravitation (sudden
  tides) and that in addition the interfering influence of solar corpuscular
  radiation is involved. It is known that this radiation causes geomagnetic
  disorders. Consistent with the above view it was proved that in the course
  of lunation the greatest number of geomagnetic disorders occur at a time
  close to the lunar quarters. Then, as the author proved--aurora polaris is
  more frequent. The increased cardiovascular mortality is thus associated
  with an increased geomagnetic activity. The relationship is certainly not
  direct. The author indicates further trends of research to disclose the
  immediate causes which exert an unfavourable effect on our cardiovascular

      Ian York   (  <>
      "-but as he was a York, I am rather inclined to suppose him a
       very respectable Man." -Jane Austen, The History of England

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