Irene Petersen

Research output

Research output per year 2015 2016 2017 2018 2019 2020 2023

• 55 Journal article
• 3 Conference abstract for conference
• 2 Comment/debate/letter to the editor
• 1 Poster
• 1 More
  • 1 Review

Research output per year

Research output per year

Search results

• 2023

  Adherence to 5-aminosalicylic acid maintenance treatment in young people with ulcerative colitis: a retrospective cohort study in primary care

  Jayasooriya, N., Pollok, R. C., Blackwell, J., Bottle, A., Petersen, I., Creese, H., Saxena, S. & POP-IBD Study Group, Nov 2023, In: The British journal of general practice : the journal of the Royal College of General Practitioners. 73, 736, p. e850-e857 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Letter: delays to diagnosis of IBD—Challenges requiring a systematic approach. Authors’ reply

  Pollok, R. C., Jayasooriya, N., Baillie, S., Blackwell, J., Petersen, I., Bottle, A., Saxena, S. & POP-IBD Study Group, Jun 2023, In: Alimentary Pharmacology and Therapeutics. 57, 12, p. 1479-1479 1 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Comment/debate/letter to the editor › Research › peer-review

• Letter: diagnostic delay in inflammatory bowel disease-Authors' reply

  Pollok, R. C., Baillie, S., Jayasooriya, N., Blackwell, J., Petersen, I., Bottle, A., Saxena, S. & POP-IBD Study Group, May 2023, In: Alimentary Pharmacology and Therapeutics. 57, 10, p. 1205-1206 2 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Comment/debate/letter to the editor › Research › peer-review

  Open Access

• Quantifying the impact of unmeasured confounding in observational studies with the E value

  Gaster, T., Eggertsen, C. M., Støvring, H., Ehrenstein, V. & Petersen, I., 2023, In: BMJ Medicine. 2, 1, 5 p., e000366.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Systematic review with meta-analysis: Time to diagnosis and the impact of delayed diagnosis on clinical outcomes in inflammatory bowel disease

  Jayasooriya, N., Baillie, S., Blackwell, J., Bottle, A., Petersen, I., Creese, H., Saxena, S., Pollok, R. C. & POP-IBD Study Group, Mar 2023, In: Alimentary Pharmacology and Therapeutics. 57, 6, p. 635-652 18 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access
• 2022

  Antidepressant medication use in Inflammatory Bowel Disease: a nationally representative population-based study

  Jayasooriya, N., Blackwell, J., Saxena, S., Bottle, A., Petersen, I., Creese, H., Hotopf, M., Pollok, R. C. G. & POP-IBD Study Group, May 2022, In: Alimentary Pharmacology and Therapeutics. 55, 10, p. 1330-1341 12 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access
  1 Citation (Scopus)

• In utero exposure to glucocorticoids and risk of anxiety and depression in childhood or adolescence

  Laugesen, K., Sørensen, H. T., Jørgensen, J. O. L. & Petersen, I., 13 Apr 2022, (E-pub ahead of print) In: Psychoneuroendocrinology. 141, p. 105766 105766.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Prenatal exposure to glucocorticoids and the prevalence of overweight or obesity in childhood

  Laugesen, K., Sørensen, H. T., Jørgensen, J. O. L. & Petersen, I., 22 Feb 2022, In: European Journal of Endocrinology. 186, 4, p. 429-440 12 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

  File
  1 Downloads (Pure)

• Stoma Formation in Crohn's Disease and the Likelihood of Antidepressant Use: A Population-Based Cohort Study

  Blackwell, J., Saxena, S., Jayasooriya, N., Petersen, I., Hotopf, M., Creese, H., Bottle, A., Pollok, R. C. G. & POP-IBD Study Group, Apr 2022, In: Clinical Gastroenterology and Hepatology. 20, 4, p. e703-e710 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review
• 2021

  Depression in individuals who subsequently develop inflammatory bowel disease: A population-based nested case-control study

  Blackwell, J., Saxena, S., Petersen, I., Hotopf, M., Creese, H., Bottle, A., Alexakis, C. & Pollok, R. C., Sept 2021, In: Gut. 70, 9, p. 1642-1648 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review
  6 Citations (Scopus)

• Extreme diurnal temperature range and cardiovascular emergency hospitalisations in a Mediterranean region

  Ponjoan, A., Blanch, J., Alves-Cabratosa, L., Marti Lluch, R., Comas-Cufi, M., Parramon, D., Garcia-Gil, M. M., Ramos, R. & Petersen, I., Jan 2021, In: Occupational and Environmental Medicine. 78, 1, p. 62-68 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Hospital variation in the risk of infection after hip fracture surgery: a population-based cohort study including 29,598 patients from 2012–2017

  Vesterager, J. D., Kristensen, P. K., Petersen, I. & Pedersen, A. B., 2021, In: Acta Orthopaedica. 92, 2, p. 215-221 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Infections in temporal proximity to HPV vaccination and adverse effects following vaccination in Denmark: A nationwide register-based cohort study and case-crossover analysis

  Krogsgaard, L. W., Petersen, I., Plana-Ripoll, O., Bech, B. H., Lützen, T. H., Thomsen, R. W. & Rytter, D., Sept 2021, In: PLOS Medicine. 18, 9, 16 p., 1003768.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Predictive values for different cancers and inflammatory bowel disease of 6 common abdominal symptoms among more than 1.9 million primary care patients in the UK: A cohort study

  Herbert, A., Rafiq, M., Pham, T. M., Renzi, C., Abel, G. A., Price, S., Hamilton, W., Petersen, I. & Lyratzopoulos, G., Aug 2021, In: PLOS Medicine. 18, 8, e1003708.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Prevalence and Duration of Gastrointestinal Symptoms before Diagnosis of Inflammatory Bowel Disease and Predictors of Timely Specialist Review: A Population-Based Study

  Blackwell, J., Saxena, S., Jayasooriya, N., Bottle, A., Petersen, I., Hotopf, M., Alexakis, C. & Pollok, R. C., 1 Feb 2021, In: Journal of Crohn's and Colitis. 15, 2, p. 203-211 9 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Review › Research › peer-review

  Open Access
  3 Citations (Scopus)
• 2020

  Combined hormonal contraceptive use in Europe before and after the European Commission mandated changes in product information

  Khialani, D., Jones, M. E., Szépligeti, S. K., Ording, A. G., Ehrenstein, V., Petersen, I. & van Hylckama Vlieg, A., 2020, In: Contraception: X. 2, 6 p., 100018.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Effects of long-term antipsychotics treatment on body weight: A population-based cohort study

  Bazo-Alvarez, J. C., Morris, T. P., Carpenter, J. R., Hayes, J. F. & Petersen, I., Jan 2020, In: Journal of Psychopharmacology. 34, 1, p. 79-85 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

  File
  15 Downloads (Pure)

• Handling missing values in interrupted time series analysis of longitudinal individual-level data

  Bazo-Alvarez, J. C., Morris, T. P., Pham, T. M., Carpenter, J. R. & Petersen, I., 2020, In: Clinical epidemiology. 12, p. 1045-1057 13 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Hospital Records of Pain, Fatigue, or Circulatory Symptoms in Girls Exposed to Human Papillomavirus Vaccination: Cohort, Self-controlled Case Series, and Population Time Trend Studies

  Thomsen, R. W., Öztürk, B., Pedersen, L., Nicolaisen, S. K., Petersen, I., Olsen, J. & Sørensen, H. T., Apr 2020, In: American Journal of Epidemiology. 189, 4, p. 277-285 9 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

  File
  34 Downloads (Pure)

• Hospital variation in the incidence of post-operative infection among hip fracture patients

  Vesterager, J. D., Kristensen, P. K., Petersen, I. & Pedersen, A. B., 2020.

  Research output: Contribution to conference › Poster › Research › peer-review

• Hospital variation in the incidence of post-operative infection among hip fracture patients

  Vesterager, J. D., Kristensen, P. K., Petersen, I. & Pedersen, A. B., 2020.

  Research output: Contribution to conference › Conference abstract for conference › Research › peer-review

• Impact of being eligible for type 2 diabetes treatment on all-cause mortality and cardiovascular events: Regression discontinuity design study

  Petersen, I., Nicolaisen, S. K., Ricciardi, F., Sharma, M., Thomsen, R. W., Baio, G. & Pedersen, L., 2020, In: Clinical epidemiology. 12, p. 569-577 9 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Three quarters of people with SARS-CoV-2 infection are asymptomatic: Analysis of english household survey data

  Petersen, I. & Phillips, A., Oct 2020, In: Clinical epidemiology. 12, p. 1039-1043 5 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access
• 2019

  Antidepressant use during pregnancy and risk of congenital heart defects: A case-time-control study

  Sun, Y., Pedersen, L. H., Wu, C. S., Petersen, I., Sørensen, H. T. & Olsen, J., 1 Sept 2019, In: Pharmacoepidemiology and Drug Safety. 28, 9, p. 1180-1193 14 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Clinical indicators of adrenal insufficiency following discontinuation of oral glucocorticoid therapy: A Danish population-based self-controlled case series analysis

  Laugesen, K., Petersen, I., Sørensen, H. T. & Jørgensen, J. O. L., 2019, In: PLOS ONE. 14, 2, 15 p., e0212259.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Comparative effectiveness of sitagliptin vs sulphonylureas in older people

  Sharma, M., Nazareth, I. & Petersen, I., 2019, In: Age and Ageing. 48, 5, p. 725-732 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Elevated vitamin B12 levels and cancer risk in UK primary care: a THIN database cohort study

  Arendt, J. F., Sorensen, H. T., Horsfall, L. J. & Petersen, I., Apr 2019, In: Cancer Epidemiology, Biomarkers & Prevention. 28, 4, p. 814-821 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Ethnic Differences in the Prevalence of Type 2 Diabetes Diagnoses in the UK: Cross-Sectional Analysis of the Health Improvement Network Primary Care Database

  Tra My Pham, Carpenter, J. R., Morris, T. P., Sharma, M. & Petersen, I., Dec 2019, In: Clinical epidemiology. 11, p. 1081-1088 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Fifteen-year nationwide trends in systemic glucocorticoid drug use in Denmark

  Laugesen, K., Jorgensen, J. O. L., Petersen, I. & Sørensen, H. T., Sept 2019, In: European Journal of Endocrinology. 181, 3, p. 267-273 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Health indicator recording in UK primary care electronic health records: key implications for handling missing data

  Petersen, I., Welch, C. A., Nazareth, I., Walters, K., Marston, L., Morris, R. W., Carpenter, J. R., Morris, T. P. & Tra My Pham, 2019, In: Clinical epidemiology. 11, p. 157-167 11 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Hospital variation in the incidence of post-operative infection among hip fracture patients

  Vesterager, J. D., Kristensen, P. K., Petersen, I. & Pedersen, A. B., 25 Oct 2019.

  Research output: Contribution to conference › Conference abstract for conference › Research › peer-review

• Hospital variation in the incidence of post-operative infection among hip fracture patients

  Vesterager, J. D., Kristensen, P. K. & Petersen, I., 27 Oct 2019.

  Research output: Contribution to conference › Conference abstract for conference › Research › peer-review

• La declaration RECORD (Reporting of Studies Conducted Using Observational Routinely Collected Health Data): directives pour la communication des etudes realisees a partir de donnees de sante collectees en routine

  Sorensen, H. T. & Com Travail RECORD, 25 Feb 2019, In: CMAJ. 191, 8, p. E216-E230 15 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• La déclaration RECORD-PE (Reporting of Studies Conducted Using Observational Routinely Collected Health Data Statement for Pharmacoepdemiology): directives pour la communication des études realisées à partir de données de santé observationelles collectées en routine en pharmacoépidémiologie

  Langan, S. M., Schmidt, S. A. J., Wing, K., Ehrenstein, V., Nicholls, S. G., Filion, K. B., Klungel, O., Petersen, I., Sørensen, H. T., Dixon, W. G., Guttmann, A., Harron, K., Hemkens, L. G., Moher, D., Schneeweiss, S., Smeeth, L., Sturkenboom, M., von Elm, E., Wang, S. V. & Benchimol, E. I., Jun 2019, In: CMAJ. 191, 25, p. E689-E708 20 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Observational studies of treatment effectiveness: worthwhile or worthless?

  Sharma, M., Nazareth, I. & Petersen, I., 2019, In: Clinical epidemiology. 11, p. 35-42 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Prevalence of lifestyle characteristics in glucocorticoid users and non-users: A Danish population-based cross-sectional study

  Laugesen, K., Petersen, I., Pedersen, L., Breinholt Larsen, F., Jørgensen, J. O. L. & Sørensen, H. T. T., 2019, In: BMJ Open. 9, 10, 9 p., e030780.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

• Selective serotonin reuptake inhibitor use in hip fracture patients: a Danish nationwide prevalence study

  Bruun, S. B., Petersen, I., Kristensen, N. R., Cronin-Fenton, D. & Pedersen, A. B., Jan 2019, In: Acta Orthopaedica. 90, 1, p. 33-39 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review
• 2018

  Depression, depressive symptoms and treatments in women who have recently given birth: UK cohort study

  Petersen, I., Peltola, T., Kaski, S., Walters, K. R. & Hardoon, S., 24 Oct 2018, In: BMJ Open. 8, 10, p. e022152 8 p., e022152.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Effectiveness of live attenuated influenza vaccine in preventing amoxicillin prescribing in preschool children: a self-controlled case series study

  Hardelid, P., Ghebremichael-Weldeselassie, Y., Whitaker, H., Rait, G., Gilbert, R. & Petersen, I., 1 Mar 2018, In: Journal of Antimicrobial Chemotherapy. 73, 3, p. 779-786 8 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Effectiveness of Statins as Primary Prevention in People With Different Cardiovascular Risk: A Population-Based Cohort Study

  Garcia-Gil, M., Comas-Cufí, M., Blanch, J., Martí, R., Ponjoan, A., Alves-Cabratosa, L., Petersen, I., Marrugat, J., Elosua, R., Grau, M. & Ramos, R., Oct 2018, In: Clinical Pharmacology and Therapeutics. 104, 4, p. 719-732 14 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

  File
  57 Downloads (Pure)

• Selective serotonin reuptake inhibitor use and mortality, postoperative complications, and quality of care in hip fracture patients: a Danish nationwide cohort study

  Bruun, S. B., Petersen, I., Kristensen, N. R., Cronin-Fenton, D. & Pedersen, A. B., 2018, In: Clinical epidemiology. 10, p. 1053-1071 19 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Statin prescribing for prevention of cardiovascular disease amongst people with severe mental illness: Cohort study in UK primary care

  Blackburn, R., Osborn, D., Walters, K., Nazareth, I. & Petersen, I., 1 Feb 2018, In: Schizophrenia Research. 192, p. 219-225 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access

  File
  2 Citations (Scopus)

  80 Downloads (Pure)

• The impact of different strategies to handle missing data on both precision and bias in a drug safety study: A multidatabase multinational population-based cohort study

  Martín-Merino, E., Calderón-Larrañaga, A., Hawley, S., Poblador-Plou, B., Llorente-García, A., Petersen, I. & Prieto-Alhambra, D., 5 Jun 2018, In: Clinical epidemiology. 10, p. 643-654 12 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• The reporting of studies conducted using observational routinely collected health data statement for pharmacoepidemiology (RECORD-PE)

  Langan, S. M., Schmidt, S. A., Wing, K., Ehrenstein, V., Nicholls, S. G., Filion, K. B., Klungel, O., Petersen, I., Sorensen, H. T., Dixon, W. G., Guttmann, A., Harron, K., Hemkens, L. G., Moher, D., Schneeweiss, S., Smeeth, L., Sturkenboom, M., von Elm, E., Wang, S. V. & Benchimol, E. I., 14 Nov 2018, In: The BMJ. 363, p. k3532 k3532.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Trends in dementia diagnosis rates in UK ethnic groups*: analysis of UK primary care data

  Pham, T. M., Petersen, I., Walters, K., Raine, R., Manthorpe, J., Mukadam, N. & Cooper, C., 2018, In: Clinical epidemiology. 10, p. 949-960 12 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review
• 2017

  Antibiotic prescribing frequency amongst patients in primary care: a cohort study using electronic health records

  Shallcross, L., Beckley, N., Rait, G., Hayward, A. & Petersen, I., Jun 2017, In: Journal of Antimicrobial Chemotherapy. 72, 6, p. 1818-1824 7 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Antiepileptic drugs prescribed in pregnancy and prevalence of major congenital malformations: comparative prevalence studies

  Petersen, I., Collings, S-L., McCrea, R. L., Nazareth, I., Osborn, D. P., Cowen, P. J. & Sammon, C. J., 2017, In: Clinical epidemiology. 9, p. 95-103 9 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Effects of extreme temperatures on cardiovascular emergency hospitalizations in a Mediterranean region: a self-controlled case series study

  Ponjoan, A., Blanch, J., Alves-Cabratosa, L., Marti-Lluch, R., Comas-Cufi, M., Parramon, D., Garcia-Gil, M. D. M., Ramos, R. & Petersen, I., 4 Apr 2017, In: Environmental Health: A Global Access Science Source. 16, 1, 9 p., 32.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Missing data and multiple imputation in clinical epidemiological research

  Pedersen, A. B., Mikkelsen, E. M., Cronin Fenton, D., Kristensen, N. R., Pham, T. M., Pedersen, L. & Petersen, I., 2017, In: Clinical epidemiology. 9, p. 157-166 10 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

• Prescription duration and treatment episodes in oral glucocorticoid users: application of the parametric waiting time distribution

  Laugesen, K., Støvring, H., Hallas, J., Pottegård, A., Jørgensen, J. O. L., Sørensen, H. T. & Petersen, I., 2017, In: Clinical epidemiology. 9, p. 591-600 10 p.

  Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaper › Journal article › Research › peer-review

  Open Access