Abstract
Background: Seasonal patterns are assumed in many fields of medicine. However, biological processes are full of variations and the possibility of chance findings can often not be ruled out.
Methods: Using simulated data we assess whether autocorrelation is helpful to minimize chance findings and test to support the presence of seasonality.
Results: Autocorrelation required to cut time curves into pieces. These pieces were compared with one another using linear regression analysis. Four examples with imperfect data are given. In spite of substantial differences in the data between the first and second year of observation, and in spite of otherwise inconsistent patterns, significant positive autocorrelations were constantly demonstrated with correlation coefficients around 0.40 (SE 0.14).
Conclusions: Our data suggest that autocorrelation is helpful to support the presence of seasonality of disease, and that it does so even with imperfect data.
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Articles in the same Issue
- Masthead
- Masthead
- Editorials
- Phlebotomy, stat testing and laboratory organization: an intriguing relationship
- Human epididymis protein 4: the start of a post-ROMAn era?
- Hyperhomocysteinemia in health and disease: where we are now, and where do we go from here?
- Reviews
- The usefulness of cystatin C and related formulae in pediatrics
- The emerging role of biomarkers and bio-impedance in evaluating hydration status in patients with acute heart failure
- Biomarkers in primary open angle glaucoma
- Mini Review
- Identification of circulating microRNAs as biomarkers in cancers: what have we got?
- Opinion Paper
- HE4 in gynecological cancers: report of a European investigators and experts meeting
- Guidelines and Recommendations
- Position paper on laboratory testing for patients taking new oral anticoagulants. Consensus document of FCSA, SIMeL, SIBioC and CISMEL1)
- General Clinical Chemistry and Laboratory Medicine
- Reducing the number of clinical stat phlebotomy orders: feasible or not?
- Calculating acid-base and oxygenation status during COPD exacerbation using mathematically arterialised venous blood
- UrineCART, a machine learning method for establishment of review rules based on UF-1000i flow cytometry and dipstick or reflectance photometer
- Reference Values and Biological Variations
- Assessing seasonality in clinical research
- Cancer Diagnostics
- Identification of a novel in-frame deletion in BRCA2 and analysis of variants of BRCA1/2 in Italian patients affected with hereditary breast and ovarian cancer
- Human epididymis protein 4 (HE4) in benign and malignant diseases
- Human epididymis protein 4 as a serum marker for diagnosis of endometrial carcinoma and prediction of clinical outcome
- A predictive equation to adjust for clinical variables in soluble mesothelin-related protein (SMRP) levels
- Cardiovascular Diseases
- Vitamin D deficiency parallels inflammation and immune activation, the Ludwigshafen Risk and Cardiovascular Health (LURIC) study
- Plasma homocysteine and the risk of venous thromboembolism: insights from the FIELD study
- Letters to the Editor
- A two-base-pairs deletion in the albumin gene causes a new case of analbuminemia
- Usefulness of an antiglycolytic granular mixture of sodium fluoride and citrate for stabilizing plasma homocysteine levels
- Further insights on the relationship between bilirubin and C-reactive protein
- Phosphoethanolamine normal range in pediatric urines for hypophosphatasia screening
- Risk of false positive hepatitis C virus RNA due to sample to sample carryover on an automated hematology analyzer
- Lack of commutability between a quality control material and plasma samples in a troponin I measurement system
- Biological variation in pregnancy-associated plasma protein-A in healthy men and non-pregnant healthy women
- Investigation of a slope discontinuity in a patients’ results distribution for D-dimer
- Acknowledgment
- Acknowledgment
Articles in the same Issue
- Masthead
- Masthead
- Editorials
- Phlebotomy, stat testing and laboratory organization: an intriguing relationship
- Human epididymis protein 4: the start of a post-ROMAn era?
- Hyperhomocysteinemia in health and disease: where we are now, and where do we go from here?
- Reviews
- The usefulness of cystatin C and related formulae in pediatrics
- The emerging role of biomarkers and bio-impedance in evaluating hydration status in patients with acute heart failure
- Biomarkers in primary open angle glaucoma
- Mini Review
- Identification of circulating microRNAs as biomarkers in cancers: what have we got?
- Opinion Paper
- HE4 in gynecological cancers: report of a European investigators and experts meeting
- Guidelines and Recommendations
- Position paper on laboratory testing for patients taking new oral anticoagulants. Consensus document of FCSA, SIMeL, SIBioC and CISMEL1)
- General Clinical Chemistry and Laboratory Medicine
- Reducing the number of clinical stat phlebotomy orders: feasible or not?
- Calculating acid-base and oxygenation status during COPD exacerbation using mathematically arterialised venous blood
- UrineCART, a machine learning method for establishment of review rules based on UF-1000i flow cytometry and dipstick or reflectance photometer
- Reference Values and Biological Variations
- Assessing seasonality in clinical research
- Cancer Diagnostics
- Identification of a novel in-frame deletion in BRCA2 and analysis of variants of BRCA1/2 in Italian patients affected with hereditary breast and ovarian cancer
- Human epididymis protein 4 (HE4) in benign and malignant diseases
- Human epididymis protein 4 as a serum marker for diagnosis of endometrial carcinoma and prediction of clinical outcome
- A predictive equation to adjust for clinical variables in soluble mesothelin-related protein (SMRP) levels
- Cardiovascular Diseases
- Vitamin D deficiency parallels inflammation and immune activation, the Ludwigshafen Risk and Cardiovascular Health (LURIC) study
- Plasma homocysteine and the risk of venous thromboembolism: insights from the FIELD study
- Letters to the Editor
- A two-base-pairs deletion in the albumin gene causes a new case of analbuminemia
- Usefulness of an antiglycolytic granular mixture of sodium fluoride and citrate for stabilizing plasma homocysteine levels
- Further insights on the relationship between bilirubin and C-reactive protein
- Phosphoethanolamine normal range in pediatric urines for hypophosphatasia screening
- Risk of false positive hepatitis C virus RNA due to sample to sample carryover on an automated hematology analyzer
- Lack of commutability between a quality control material and plasma samples in a troponin I measurement system
- Biological variation in pregnancy-associated plasma protein-A in healthy men and non-pregnant healthy women
- Investigation of a slope discontinuity in a patients’ results distribution for D-dimer
- Acknowledgment
- Acknowledgment