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Cross-cultural investigation of fibromyalgia epidemiology to identify contributing factors.



Cross-cultural investigation of fibromyalgia to identify epidemiology factors. The hypothesis is that it's worse to be living in Australia than New Zealand for aggravation of fibromyalgia symptoms. The study proposes a controlled synthesis of a pilot grounded in the data of social networking reports, intersecting anthropology with pathophysiology to reveal factors which influence prevalence of this syndrome.
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Cross-cultural investigation of fibromyalgia to identify epidemiology factors.
The hypothesis is that it’s worse to be living in Australia than New Zealand for aggravation of
fibromyalgia symptoms. The study proposes a controlled synthesis of a trial grounded in the
data of social networking reports, intersecting anthropology with pathophysiology to reveal
factors which influence prevalence of this syndrome.
Background to the Aims. Fibromyalgia (FM) is seen as an immunological disorder, diagnosed by
the 1990 American College of Rheumatology (ACR) criteria of pain at 11 or more of 18 points.
Prevalence of FM detected under these criteria could be one sixth
of that using the 2010 ACR,
which was broadened to include widespread pain - thus facilitating assessment by survey but
with reduced test sensitivity. Cross-sectional studies could highlight ecological, societal stress as
a possible cause but collection of detailed individual parameters is required to adjust for
confounding. Quieroz
systematic review of the literature alongside Klemp’s study from
(since New Zealand was overlooked) alludes to extremes of prevalence below.
Neither Australia, nor England, nor Ireland has studied prevalence, despite FM being a
debilitating disease with 41% of Monash FM outpatients on disability benefits (Guymer 2012
*n<700 Another, selective study of Turkish textile workers estimated a gender adjusted FM prevalence
of 3.6% (Cobankara). Overall female participation in Turkish workforce was only 24% in 2005.
Women only. Figure has been challenged, refer text.
Variability in crude rates could be partially attributed to the lack of age stratification, which is
expected to show case accrual since the syndrome has no cure. The inability of the healthcare
system to intercept cases could also be a major factor affecting ethnology assumptions. This is
investigated in a pilot study, which yields preliminary insights.
A population was chosen to investigate this variability and also profile symptom severity of the
FM patient by means of regression, which could be used as a proxy for risk of disease
progression between countries. A Patient Reported Outcome website (PatientsLikeMe, PLM)
provided just 40 NZ, and 14 Baltic region diagnosed cases between Finland, Denmark and
Sweden. Norway has been excluded since the prevalence data is suspected of bias following
disclosure of particular regions where a diagnosis is easier, in order to exploit a generous
national disability scheme. 70 Canadian cases (stratified to redress gender imbalance) were
selected from 960 subscribers, to match climatic conditions with Baltic states. Likewise 45
Australian cases were selected from 310 for comparison with NZ, on the basis of most recent
blog activity. The mean times between symptoms and clinical diagnosis of FM for Baltic regions,
NZ, Australia, and Canada were 10, 8.9, 10.1 and 9.2 years respectively. Median times for NZ,
Australia, and Canada were 3.0 years and the annexed diagram displays this commonality,
inferring that reported prevalence differences do not arise due to diagnostic tardiness. Six
subscribers are from India their inclusion is of interest but statistically inconclusive.
Fibromyalgia is understood to arise subsequent to distress, and unpaired t-test was used to
ascertain cultural factors in stress measured on a scale of 0-4 (none overwhelming). Canadian
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average of 2.35 is significantly higher than Baltic regions 1.40 (p=0.012) but New Zealand’s
lower stress mean of 2.03 is insignificant (p=0.2) largely due to 18% of declining to answer. In
order to test severity of symptoms for correspondence to prevalence the Pain Fatigue Rating
Scale (PFRS) from 0-50 (questions appended) routinely submitted by subscribers has been used.
This survey rated significantly better for NZ residents than Canadian: mean of 30.4 against 35.6
(p=0.007). The average for Australia of 37.2 begs the question what would the prevalence be
here? The emphasis on exacerbation factors within two purposively selected patient
communities reduces the cohort of a large population random sample that would be required
for examination of disease prevalence. Recruitment is enhanced by the vested interest of
support forum subscribers in finding solutions, whereas general population awareness is poor.
Thus the surrogate outcome of risk factors is the PFRS, further validation follows below.
Confounders. Adherence to medication depends on perceived effectiveness. Determining the
five most effective drugs was done by likelihood of those receiving treatment being in the
lowest quintile of PFRS, ie below 30 (worldwide n=19442). OR for corticoid prednisolone, SSNI
desvenlafaxine, NSAID celecoxib, and TCA amitryptiline were 1.22, 1.51, 1.24 and 1.18
respectively. Prescriptions of these four were higher in Australia than Canada (20% of 310 and
15% of 959 subscribers respectively). Limited statistical significance (p>0.05) can be attached to
the use of these by 36% of New Zealanders.
The three US FDA approved medications for FM - SNRIs duloxetine and milnacipran and
anticonvulsant pregabalin were as ineffective as opioids, since OR= 1.05 (avg of 4 drugs) in
improving PFRS to below 30. 28% of Canadians and 32% of Australian subscribers had been
prescribed these three medications, but no New Zealanders. Individual responses must be
sought to explain the OR(PFRS<30)=3.0 for NZ residents as a phenomena, compared to
Australia’s 0.85 since no conclusion can be drawn on ecological data as it stands. Drug
effectiveness must be included - the Cochrane Collaboration published a systematic review of 5
independent trials each of duloxetine & milnacipran, finding a small incremental benefit over
placebo in reducing pain”
only. Reporting on 5 pregabalin trials against a placebo found “slight
reduction in pain, fatigue and sleep problems”.
De-confounding can begin with globalization indices, many being available. Defined as the
intensification of worldwide social relations which link distant localities in such a way that local
happenings are shaped by events occurring many miles away and vice versa in the index
chosen, for its reflection of actual cultural change.
Danish lexicon has an opposite concept:
‘hygge’ meaning cosiness, shutting out the turmoil of the outside world. Along with Milner’s
index from Griffith University is shown the World Economic Forum Gender Gap ranking. Sex
discrimination in the workforce would appear comparable between Australia and NZ for the
past 6 years the male female disparity in workforce participation has been ~15% for both
although it worsens somewhat for older Australian women.
WEF Genderviii
Disempowerment as measured by globalization clearly goes some way to explain severity of FM
in Australia against NZ, overriding any increase in stress resultant from living on a fault-line.
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Although the two societies are expected to have much in common, a qualitative study quoted a
medical researcher’s complaint
Australia has a much more defensive bureaucracy....... in
New Zealand, at least my dealings ethics committees have been seen as much more
a facilitator role, saying this is good research, how can we best facilitate it actually being
A model of PFRS for a well studied strata is appropriate, to determine further lines of inquiry in
questionnaire. Significant factors found when modeling the Canadian patients were Gender,
Stress level, and co-morbidities (both Psychiatric disorders and Chronic-nonInflammatory),
which yielded a correlation coefficient of r=0.69 : adjusted R2=0.44
PFRS = 35.5 + 3.4*Stress + 6.7*Psych 6.6*Female 6.9*nonInflamm (There was strong
significance for both co-morbidities p=0.001, and Stress p=0.000)
Impact of Overwhelming level stress of 4 increasing Pain&Fatigue score by 13 is unsurprising,
likewise presence of mental disturbances. Women appear to cope better, but PFRS
improvement due to presence of a chronic comorbidity requires exploring perhaps the
possibility of stronger belief in medication effectiveness and hence adherence. Age reduced
PFRS by 0.5 per decade but p>0.5, nonetheless it points to acceptance coming with time.
Limitations. The pilot data are unadjusted crude ratios, furthermore a decision was made not
to extract from case histories any temporal association between the most recent PFRS against
either current or discontinued medication. Treatments perceived as ineffective may well have
been prescribed ‘in extremis’ once all else failed. Diet and in particular the Ω-3/Ω-6 ratio could
also be compared. None of the NZ subscribers declared Fish Oil/OmegaΩ-3 supplements as a
treatment, despite it showing outstanding effectiveness worldwide OR=2.1 of having
PFRS<30. Despite seemingly obvious disparities - such as NZ’s kumara alternative to the
nightshade family potato, excessive study complexity will result. The proportion of FM patients
declaring Type II diabetes (3.8%) and obesity (1.4%) is in accord with rates for the total 236,000
subscribers even before fatigue as an impediment to exercise is factored in. The oft-raised
complaint of weight gain on anti-depressants is countered by loss due to IBS, but opinions
expressed in forums indicate that a healthy diet is always desired. Selection bias arises from the
proportion of women using online FM support groups exceeding men 20:1 when diagnosed FM
cases affect a ratio of 6:1 in the community. This discrepancy may become a fallacy when the
general population is surveyed, as the Olmsted County survey indicatesi. Sufficient men were
actively sought from Canadian patients in order to create a significance in the regression model
of p=0.03 for gender.
Significance. The potential to reconsider preferences in prescribing medications is apparent.
Further work would be required to investigate dosage advisories and pharmacogenetics may
mature sufficiently to inform anti-depressant appropriateness. Issues of gender equality are
already in focus, however associating a human cost in disease would strengthen the arguments.
Objective. A comparison of symptom severity between Australian and New Zealand resident
fibromyalgia patients, factored by medication adherence and sense of empowerment.
Design. Analytical cross sectional study by survey.
Setting. The population has been drawn from subscribers to an online support network.
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Exposure criteria. The risk of immigration weakens any association between symptom severity
and prevalence so inclusion is limited to lifelong residents with a clinical diagnosis of
Outcome measures. Pain and fatigue currently experienced, using a modified scoring which
includes sleep disturbance.
Power. To confirm a hypothesis of trans-Tasman differences, study population for 80% power in
confirming the PFRS difference of 37.2-30.4=6.8 is easily calculated. SD in pilot data=8.4 so
assuming a normal distribution:
n=(1.96+0.84 *8.4/6.8)2 = at least ~12 from each country.
For each of the confounders gender, co-morbidities and stress 10% can be added per Breslow
and Day (1987) requiring a total of 32 subscribers. The ambition of explaining 44% of the causes
in PFRS difference per the Canadian model requires that interaction between the country and
characteristics of the strata be detected, for which a quadrupling of numbers for overall
association is advised
, thus 50 per country.
Ethics. The holder of the IP to the pilot study has granted approval to reproduce any data which
is already accessible from public queries. Should direct patient contact be sought through PLM,
a proportion of funding will be charged if a grant for the study partner is obtained. Open
FaceBook Fibro Support groups already number 4200 in Australia, 160 in NZ. These should
suffice for recruitment to survey instead of the PLM site.
Consent to participation without contact by the 170 PLM subscribers who provided the trial
data is implied when agreeing to the FAQ Most healthcare websites have a Privacy Policy.
Naturally, we do too. But at PatientsLikeMe, we’re more excited about our Openness
Philosophy. It may sound counterintuitive, but it’s what drives our groundbreaking concept
Currently, most healthcare data is inaccessible due to privacy regulations or proprietary tactics.
As a result, research is slowed, and the development of breakthrough treatments takes
The PFRS is licensed under Creative Commons ©© to be freely used or adapted as
Measurement tools. Further investigation should validate the temporality of treatments and
outcome, which is missing in the pilot queries of the database. Data collection is to be completely
de-identified with the exception of a sequence number issued to the participant, should they
wish to withdraw from the study prior to publish. An outline of the survey must cover:
Medication. Current (prescription & dosage compliance), previous - also reasons withdrawn
Age, gender. Diagnosis confirmed by either doctor/rheumatologist and what date?
Other ailments. Medication taken, and perceived effectiveness?
Other symptoms. Memory or comprehension or concentration difficulties, teeth grinding,
rashes, dry mouth or eyes, senses sensitivity, migraine headaches.
Self-discipline. Empowered control over fight or flight reactions. Healthy dietary decisions.
A validated arthritic score the shortform HAQ-II is required, but as an adjunct by setting a
baseline to the model using symptom recall from the time of diagnosis. 100 respondents is the
cutoff for free usage of SurveyMonkey©, and access to SPSS v19 is available. The following
PFRS questions incorporating the sleep score also must be incorporated in any survey for
compatibility with extant data.
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Appendix PFRS ©© PatientsLikeMe
On a scale of 0-4: How often did you ….experience pain? have deep, aching pain? have radiating
pain? have gnawing pain? have shooting pain? have burning sensations? have trouble falling
asleep? have trouble getting enough sleep? wake up without feeling rested? wake with muscle
or body aches? wake with joint stiffness? have problems working or doing daily activities? have
problems relating to friends, family, or co-workers? have problems organizing tasks or
activities? felt tired for no good reason? needed to stay in bed or a chair most of the time
during the day because of fatigue?
On a scale of 0-10 How severe have been ….pain? fatigue?
Table1. Aggregated data for crude odds ratios.
Updated 19 Dec 2013
Total FM subscribers
Hydrocodone / Oxycodone
Adalimumab / Etanercept
Melatonin or Vitamin-D (-takes
73 (-17)
206 (-38)
Fish oil / Omega3 supplements
Lithium Carbonate
Of note is the significant(χ2=25) lithium usage improvement in PFRS, prescribed for the 0.46%
of FM subsribers with a Bipolar comorbidity. This should be investigated as evidence of the
merit of pacing, in moderating manic episodes lest plummeting into post-exertional malaise
ensues. Alternative medicine is endorsed by 10% of Australians, 11% of Canadians and 27% of
New Zealanders, however OR=1.04 discounts this factor.
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Diagram1. Pilot study data showing time to obtain a diagnosis from recall of first symptom.
Vincent A, St Sauver J et al. Prevalence of Fibromyalgia: A Population-Based
Study in Olmsted County, Minnesota, Utilizing theRochester Epidemiology Project. Arthritis Care & Research 2013;
65: 786
Quieroz L. Worldwide Epidemiology of Fibromyalgia. Curr Pain Headache Rep. 2013; 17:356-
Klemp P, Williams S, Standfield S. Fibromyalgia in Maori and European New Zealanders. APLAR Journal of
Rheumatology 2002;5: 15
Guymer E, Maruff P, Littlejohn G. Clinical characteristics of 150 consecutive fibromyalgia patients attending an
Australian public hospital clinic. International Journal of Rheumatic Diseases 2012; 15: 348357
Häuser W, Urrútia G, Walitt B et al. Serotonin and noradrenaline reuptake inhibitors (SNRIs) for fibromyalgia
syndrome (Review). Wiley 2013
Üçeyler N, Sommer C, Walitt B, Häuser W. Anticonvulsants for fibromyalgia (Review). Wiley 2013
Milner A et al. Globalisation and suicide: An empirical investigation in 35 countries over the period 19802006.
Health & Place 2011; 17: 996-1003
Gillam L, Guillemin M et al. Human Research Ethics in Practice. MONASH BIOETHICS REVIEW, 2009; 28: 07,
Kirkwood B, Sterne J. Essential Medical Statistics. Blackwell Science, 2009
ResearchGate has not been able to resolve any citations for this publication.
Full-text available
Studying the epidemiology of fibromyalgia (FM) is very important to understand the impact of this disorder on persons, families and society. The recent modified 2010 classification criteria of the American College of Rheumatology (ACR), without the need of tender points palpation, allows that larger and nationwide surveys may be done, worldwide. This article reviews the prevalence and incidence studies done in the general population, in several countries/continents, the prevalence of FM in special groups/settings, the association of FM with some sociodemographic characteristics of the population, and the comorbidity of FM with others disorders, especially with headaches.
Full-text available
Fibromyalgia syndrome (FMS) is a clinically well-defined chronic condition of unknown etiology characterized by chronic widespread pain that often co-exists with sleep disturbances, cognitive dysfunction and fatigue. Patients often report high disability levels and poor quality of life (QOL). Drug therapy focuses on reducing key symptoms and improving quality of life. To assess the benefits and harms of serotonin and noradrenaline reuptake inhibitors (SNRIs) compared with placebo for treating FMS symptoms in adults. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), (The Cochrane Library 2012, Issue 9), MEDLINE (1966 to September 2012), EMBASE (1980 to September 2012), (U.S.-marketed pharmaceuticals) (to September 2012) and (to September 2012) for published and ongoing trials and examined the reference lists of reviewed articles. We selected randomized, controlled trials of any formulation of SNRIs against placebo for the treatment of FMS in adults. Two review authors independently extracted the data from the included studies, and assessed the risks of bias of the studies. Discrepancies were resolved by discussion. Ten studies were included with a total of 6038 participants. Five studies investigated duloxetine against placebo, and five investigated milnacipran against placebo. A total of 3611 participants were included into duloxetine or milnacipran groups and 2427 participants into placebo groups. The studies had a low risk of bias in general. Duloxetine and milnacipran had a small incremental effect over placebo in reducing pain (standardized mean difference (SMD) -0.23; 95% confidence interval (CI) -0.29 to -0.18; 6.1% relative improvement). One-hundred and ninety-two participants per 1000 on placebo reported an at least 50% pain reduction compared to 280 per 1000 on SNRIs (Risk ratio (RR) 1.49, 95% CI 1.35 to 1.64; number needed to treat to benefit (NNTB) 11, 95% CI 9 to 15). Duloxetine and milnacipran did not reduce fatigue substantially (SMD -0.14; 95% CI -0.19 to -0.08; 2.5% relative improvement; NNTB 17, 95% CI 12 to 29), and did not improve QOL substantially (SMD -0.20; 95% CI -0.25 to -0.14; 4.6% relative improvement; NNTB 12, 95% CI 9 to 17) compared to placebo. There were no statistically significant differences between either duloxetine or milnacipran and placebo in reducing sleep problems (SMD -0.07; 95% CI -0.16 to 0.03; 2.5% relative improvement). One-hundred and seven participants per 1000 on placebo dropped out due to adverse events compared to 196 per 1000 on SNRIs. The dropout rate due to adverse events in the duloxetine and milnacipran groups was statistically significantly higher than in placebo groups (RR 1.83, 95% CI 1.53 to 2.18; number needed to treat to harm (NNTH) 11, 95% CI 9 to 13). There was no statistically significant difference in serious adverse events between either duloxetine or milnacipran and placebo (RR 0.78, 95% CI 0.55 to 1.12). The SNRIs duloxetine and milnacipran provided a small incremental benefit over placebo in reducing pain. The superiority of duloxetine and milnacipran over placebo in reducing fatigue and limitations of QOL was not substantial. Duloxetine and milnacipran were not superior to placebo in reducing sleep problems. The dropout rates due to adverse events were higher for duloxetine and milnacipran than for placebo. The most frequently reported symptoms leading to stopping medication were nausea, dry mouth, constipation, headache, somnolence/dizziness and insomnia. Rare complications of both drugs may include suicidality, liver damage, abnormal bleeding, elevated blood pressure and urinary hesitation.
Objective To estimate and compare the prevalence of fibromyalgia by 2 different methods in Olmsted County, Minnesota.Methods The first method was a retrospective review of medical records of potential cases of fibromyalgia in Olmsted County using the Rochester Epidemiology Project (from January 1, 2005, to December 31, 2009) to estimate the prevalence of diagnosed fibromyalgia in clinical practice. The second method was a random survey of adults in Olmsted County using the fibromyalgia research survey criteria to estimate the percentage of responders who met the fibromyalgia research survey criteria.ResultsOf the 3,410 potential patients identified by the first method, 1,115 had a fibromyalgia diagnosis documented in the medical record by a health care provider. The age- and sex-adjusted prevalence of diagnosed fibromyalgia by this method was 1.1%. By the second method, of the 2,994 people who received the survey by mail, 830 (27.6%) responded and 44 (5.3%) met the fibromyalgia research survey criteria. The age- and sex-adjusted prevalence of fibromyalgia in the general population of Olmsted County by this method was estimated at 6.4%.Conclusion To the best of our knowledge, this is the first report of the rate at which fibromyalgia is being diagnosed in a community. This is also the first report of prevalence as assessed by the fibromyalgia research survey criteria. Our results suggest that patients, particularly men, who meet the fibromyalgia research survey criteria are unlikely to have been given a diagnosis of fibromyalgia.
To describe clinical characteristics of fibromyalgia in an Australian population. Data was collected from 150 consecutive patients with clinical features of fibromyalgia seen in an Australian public hospital clinic. Demographic information and clinical characteristics were recorded. Significant correlations between clinical characteristics were identified, then used in multiple regression analyses to identify factors influencing outcome in physical function, pain, fatigue and sleep disturbance. Clinical features in groups who were or were not using different treatment strategies were compared. Most patients were female and Caucasian. The majority reported a recognizable trigger factor and many had associated conditions, most commonly headache and irritable bowel syndrome. Physical function was significantly accounted for by pain levels (P = 0.001); pain score was significantly predicted by tenderness (P = 0.002) and physical function level (P = 0.001); fatigue levels were significantly influenced by age (P = 0.007) and sleep disturbance (P < 0.001), and sleep disturbance was significantly predicted by fatigue (P < 0.001). Just over one-third (34%) of patients were using fibromyalgia medications (low-dose tricyclic antidepressant, pregabalin or duloxetine); however, they had less anxiety (P = 0.006) and better reported physical function (P = 0.04) than those who were not. Less than half (43.6%) of the patients were regularly exercising; however, they had reduced overall illness impact scores (P = 0.004), better physical function (P = 0.01) and less fatigue (P = 0.03), anxiety (P = 0.02) and depressive features (P = 0.008) than non-exercisers. Baseline clinical characteristics in this group were comparable to other study populations. The use of management modalities with proven benefit in fibromyalgia was limited; however, those patients who were engaged in regular exercise or using medication had better self-reported outcome measures than those who were not.
Aim: The objectives of this study were to determine: (i) the prevalence of fibromyalgia (FM) in Maori and European New Zealanders; and (ii) whether an association exists between hypermobility and FM. Methods: The 1990 American College of Rheumatology classification criteria were used to determine the prevalence of FM (both criteria), widespread pain (WP) only, and a tender point score (TPS) ≥ 11 only, in subjects aged 12 years and older. Beighton's method was used to determine hypermobility. Results: The prevalence of FM in Maori (1.1%) and European (1.5%) New Zealanders was similar (an overall prevalence of 1.3%); 1.7% Maori and 3.9% Europeans had WP only; and 1.7% Maori and 0.9% Europeans had a TPS of ≥ 11 only. In Maori, the prevalence of WP and a TPS ≥ 11 were the same and similar to the prevalence of FM. In Europeans, WP was 2.6-fold more common than FM. None of the subjects with FM, WP only or a TPS ≥ 11 only was hypermobile. Conclusion: The prevalence of FM was similar in Maori and European New Zealanders, and similar to most other population studies. In Maori, WP and a TPS ≥ 11 were equally specific for FM whereas in Europeans, WP was more sensitive but less specific for FM than a TPS ≥ 11. There was no association between hypermobility and FM.
Globalisation is mediated through a variety of flows including persons, information and ideas, capital, and goods. The process is increasingly recognised as a potential mediator of changes in attitudes and habits around the globe. This research investigated the relationship between globalisation and suicide rates in 35 countries over the period 1980-2006. The association between a globalisation "index" and suicide rates was tested using a fixed-effects regression model. The model also tested the influence of eleven other socio-economic variables on male and female suicide rates. Overall, high levels of the globalisation index were associated with higher male and female suicide rates; however, the significance of this association dropped when assessed alongside other social and economic variables. While the nature of these findings should be regarded as exploratory, this paper highlights the need for researchers to consider the influence of world-changing phenomena like globalisation on suicide, which might deeply upset the traditional structure of societies with mixed types of impact.
Worldwide Epidemiology of Fibromyalgia
  • L Ii Quieroz
ii Quieroz L. Worldwide Epidemiology of Fibromyalgia. Curr Pain Headache Rep. 2013;
Anticonvulsants for fibromyalgia (Review)
  • N Vi Üçeyler
  • C Sommer
  • B Walitt
  • W Häuser
vi Üçeyler N, Sommer C, Walitt B, Häuser W. Anticonvulsants for fibromyalgia (Review). Wiley 2013
  • L Ix Gillam
  • M Guillemin
ix Gillam L, Guillemin M et al. Human Research Ethics in Practice. MONASH BIOETHICS REVIEW, 2009; 28: 07, x Kirkwood B, Sterne J. Essential Medical Statistics. Blackwell Science, 2009