Postal Invitation Research Articles

Age, Quality, and Context of First Sex: Associations With Sexual Difficulties

Research consistently indicates an association between a younger age at first sex and poorer sexual health outcomes. However, research addressing associations between age at first sex and sexual difficulties has produced mixed findings. Moreover, little is known about links between the context and quality of first sex and subsequent sexual difficulties. The aims of this study are to examine whether (i) age and (ii) context and quality at first sex are associated with sexual difficulties; (iii) examine whether age at first sex and context and quality variables are independently associated (after mutual adjustment) with sexual difficulties; and (iv) examine whether age at first sex has an indirect effect on sexual difficulties through an effect on context or quality. Data from 388 questionnaires were gathered from students aged 17-21 living in accommodation halls and by postal invitation to adults aged 25-35. The main outcome measure was the Golombok-Rust Inventory of Sexual Satisfaction (GRISS), which assesses sexual difficulties via an overall score and seven subscales. Appraising first sex as emotionally negative was associated with the majority of sexual difficulties. A less stable relationship at first sex was associated with sexual communication problems and dissatisfaction. Greater enjoyment and using substances were associated with a lower likelihood of anorgasmia for women. Age at first sex was directly associated with reduced sexual frequency only. A younger age at first sex was associated with a greater likelihood of negative appraisal and lower likelihood of a stable relationship and thereby indirectly associated with several sexual difficulties. Experiencing first sex as emotionally negative was consistently associated with later sexual difficulties. When attending to sexual difficulties, understanding the quality and context of first sex may be more useful than knowing the age at first sex. This research is limited by the retrospective nature of the reports of first sex.

Method of invitation and geographical proximity as predictors of NHS Health Check uptake.

BackgroundUptake of NHS Health Checks remains below the national target. Better understanding of predictors of uptake can inform targeting and delivery. We explored invitation method and geographical proximity as predictors of uptake in deprived urban communities.MethodsThis observational cohort study used data from all 4855 individuals invited for an NHS Health Check (September 2010–February 2014) at five general practices in Stoke-on-Trent, UK. Attendance/non-attendance was the binary outcome variable. Predictor variables included the method of invitation, general practice, demographics, deprivation and distance to Health Check location.ResultsMean attendance (61.6%) was above the city and national average, but varied by practice (47.5–83.3%; P < 0.001). Telephone/verbal invitations were associated with higher uptake than postal invitations (OR = 2.87, 95% CI = 2.26–3.64), yet significant practice-level variation remained. Distance to Health Check was not associated with attendance. Increasing age (OR = 1.04, 95% CI = 1.03–1.04), female gender (OR = 1.48, 95% CI = 1.30–1.68) and living in the least deprived areas (OR = 1.59, 95% CI = 1.23–2.05) were all independent positive predictors of attendance.ConclusionsUsing verbal or telephone invitations should be considered to improve Health Check uptake. Other differences in recruitment and delivery that might explain remaining practice-level variation in uptake warrant further exploration. Geographical proximity may not be an important predictor of uptake in urban populations.

National indicators of health literacy: ability to understand health information and to engage actively with healthcare providers - a population-based survey among Danish adults.

BackgroundHealth literacy is a multidimensional concept covering a range of cognitive and social skills necessary for participation in health care. Knowledge of health literacy levels in general populations and how health literacy levels impacts on social health inequity is lacking. The primary aim of this study was to perform a population-based assessment of dimensions of health literacy related to understanding health information and to engaging with healthcare providers. Secondly, the aim was to examine associations between socio-economic characteristics with these dimensions of health literacy.MethodsA population-based survey was conducted between January and April 2013 in the Central Denmark Region. Postal invitations were sent to a random sample of 46,354 individuals >25 years of age. Two health literacy dimensions were selected from the Health Literacy Questionnaire (HLQ™): i) Understanding health information well enough to know what to do (5 items), and ii) Ability to actively engage with health care providers (5 items). Response options ranged from 1 (very difficult) to 4 (very easy). We investigated the level of perceived difficulty of each task, and the associations between the two dimensions and socio-economic characteristics.ResultsA total of 29,473 (63.6%) responded to the survey. Between 8.8%, 95% CI: 8.4-9.2 and 20.2%, 95% CI: 19.6-20.8 of the general population perceived the health literacy tasks as difficult or very difficult at the individual item level. On the scale level, the mean rating for i) understanding health information was 3.10, 95% CI: 3.09-3.10, and 3.07, 95% CI: 3.07-3.08 for ii) engagement with health care providers. Low levels of the two dimensions were associated with low income, low education level, living alone, and to non-Danish ethnicity. Associations with sex and age differed by the specific health literacy dimension.ConclusionEstimates on two key dimensions of health literacy in a general population are now available. A substantial proportion of the Danish population perceives difficulties related to understanding health information and engaging with healthcare providers. The study supports previous findings of a socio-economic gradient in health literacy. New insight is provided on the feasibility of measuring health literacy which is of importance for optimising health systems.

Implementing a national flexible sigmoidoscopy screening program: results of the English early pilot.

Following the results of a major UK study showing that once-only flexible sigmoidoscopy (FSIG) screening significantly reduced colorectal cancer (CRC) incidence and mortality, an FSIG screening program in England was announced in late 2010. Three "early pilot" sites were selected in 2011 in Derby, South of Tyne, and Tees to assess the practicalities of the delivery of FSIG screening. Eligible people aged 55 from selected practices in the three early pilot areas received postal invitations to participate. The South of Tyne and Derby sites employed interactive models of screening invitation, while Tees used a simple invitation. Data were collected to assess uptake, process, and outcome. A self-completion participant satisfaction questionnaire was sent to all participants 1 month after attendance. A total of 4023 55-year-olds were invited to participate. Uptake was 29 %, with 1151 people screened over a 3-month period. Screening uptake differed by method of invitation: a simple approach was significantly more successful than an interactive one (32 % vs. 27 %, P = 0.0015). Uptake decreased significantly with increasing deprivation. Adenomas were found in 111 (9.8 %) of those screened and cancer in two. The procedure was rated "very" or "fairly" acceptable by 97 % of participants. Over 90 % of respondents said they would participate in future cancer screening and a similar proportion would recommend doing so to others. Delivery of an FSIG screening program to prevent CRC is feasible and should be implemented using a simple invitation system. The national Bowel Scope program subsequently commenced at pilot sites in May 2013, with full implementation planned by 2016.

Adult physical, sexual, and emotional abuse and postpartum depression, a population based, prospective study of 53,065 women in the Norwegian Mother and Child Cohort Study

BackgroundPostpartum depression (PPD) has detrimental consequences to the women, their infants and families. The aim of the present study was to assess the association between adult abuse and PPD.MethodsThis study was based on data from 53,065 pregnant women in the Norwegian Mother and Child Cohort Study (MoBa), conducted by the Norwegian Institute of Public Health. Women were recruited through a postal invitation in relation to a routine ultra-sound invitation at week 18 of gestation. Exposure to adult emotional, sexual, physical abuse was based on self-report at week 30, also differentiating if the perpetrator was known or a stranger, and whether the abuse was recent or not (<12 month since abuse). PPD was measured with a four items version of the Edinburgh Postnatal Depression Scale (EDS) at six months postpartum. The associations between different types of adult abuse and PPD were performed with logistic regression, adjusting for age, parity, civil status, education, child abuse, social support, and depression prior to pregnancy.ResultsAltogether, 11% had PPD, and 19% had been exposed to adult abuse. Women reporting adult abuse had an 80% increased fully adjusted odds of PPD (OR 1.8 95% CI 1.7-1.9) compared to non-abused women. There was a tendency towards higher odds of PPD for women reporting combinations of adult abuse (emotional, sexual and physical), as compared with those reporting sexual, emotional or physical abuse only. Exposure from known perpetrator was more strongly associated with PPD than exposure from an unknown perpetrator. Compared with women without adult abuse, the fully adjusted odds of PPD was 2.6 (95% CI 2.4-2.9) higher for women with any recent adult abuse and 1.5 (95% CI 1.5-1.7) higher for women with any adult abuse, but not recent.ConclusionsThe results from this large prospective population-based cohort study support initiatives aiming to assess and adequately address abuse when counseling and treating women of PPD.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2393-14-316) contains supplementary material, which is available to authorized users.

A randomized trial of survey participation in a national random sample of general practitioners and gynecologists in France

BackgroundHealthcare professionals play a critical role in women's choice of contraceptive methods. However, national surveys on sexual and reproductive health (SRH) among physicians are rare and present low participation rates. We conducted a randomized trial to test for the effectiveness of three interventions to improve survey participation of private physicians delivering reproductive health services in France. MethodsThe study comprised a national random sample of 500 general practitioners and 500 gynecologists working in private offices. All received a postal invitation to participate either by completing a paper, phone or online questionnaire. Physicians were randomly assigned to six groups to test for the effect of three interventions: a non-monetary incentive in the form of a scientific book, telephone contact, and the possibility of completing the questionnaire by phone. ResultsOverall, 362 questionnaires were collected (26 online, 2 by phone) and 58 physicians were ineligible. The completion rate increased from 26.7% in physicians who received no intervention to 42.7% in those who received the book and a phone call. The phone call increased the completion rate by 11% percentage points (P=0.01), while the book had no significant effect. Results from multivariate logistic regressions also indicate that gynecologists (OR=1.6) and female physicians (OR=1.5) were more likely to participate than others. ConclusionThe results suggest that phone calls substantially increase participation of physicians in sexual and reproductive health surveys but have little impact on sampling distortion. Differentials in response rates by physicians’ characteristics should be considered in future SRH studies among physicians.

Opportunistic community-based health checks

Cardiovascular disease (CVD) remains the most common cause of premature death in the UK, with considerable social inequalities and predicted increases. It is estimated that 80e90% of CVD is preventable, but this is contingent on effective programmes for screening, prevention (through modifiable risk factors) and treatment. In the UK, there are large scale CVD screening programmes delivered in primary care by health professionals. Their aim is early identification of risk or disease, which allows more effective subsequent management. For example, in England, the NHS Health Check programme involves screening adults aged 40e74yearswhoare thought tobefreefromCVDto identify (and subsequently manage) potential CVD risk or disease; the Scottish Keep Well initiative similarly aims to tackle CVD starting with health assessments in 45e64 year olds. The viability and effectiveness of such programmes depends on sufficient uptake. Evidence from large scale and national CVD health check initiatives indicates that uptake through traditional postal invitation is low (e.g., 43e49%) with various reasons posited (e.g., invitation not reaching target population; literacy/health literacy barriers; competing time commitments; preventive

Is screening for AF worthwhile? Stroke risk in a screened population from the SAFE study.

Atrial fibrillation (AF) is an important independent risk factor for stroke and oral anticoagulation therapy provides a highly effective treatment to reduce this risk. Active screening strategies improve detection of AF in comparison with routine care; however, whether screen-detected patients have stroke risk profiles favouring anticoagulation is unclear. Using data derived from the screening for AF in the elderly (SAFE) study, the aim of this article was to determine if patients with AF detected via active screening have stroke risk profiles that warrant prophylactic anticoagulation. Secondary analysis of data derived from 25 general practices within which cohorts of 200 patients were randomly allocated to opportunistic [pulse and electrocardiogram (ECG)] or systematic screening (postal invitation for ECG). Stroke risk assessment was undertaken using baseline data extracted from medical records and CHADS2 criteria. CHADS2 scores were compared between the screening groups. One hundred and forty-nine new cases of AF were detected, 75 via opportunistic screening and 74 via systematic screening. CHADS2 scores were ≥1 in 83% [95% confidence interval (CI) 72.6-89.6] of patients detected via opportunistic screening and 78% (95% CI 67.7-86.2) detected via systematic screening. There were no significant differences in stroke risk profiles of patients detected via opportunistic and systematic screenings. Stroke risk profiles of patients detected via opportunistic and systematic screenings were similar. Data derived from the SAFE study suggest that active screening for AF in patients aged ≥65 years in primary care is a useful screening programme with 78-83% of patients identified eligible for anticoagulation treatment according to the CHADS2 criteria.

Respiratory symptoms in households as an effective marker for influenza-like illness surveillance in the community

To effectively track the growth of influenza, we piloted an online system to monitor influenza-like illness (ILI) in the community in one district of Hong Kong. Four syndromic markers, namely fever, respiratory symptoms, fever with respiratory symptoms, fever and/or respiratory symptoms, either of the individual or of the household, were collected during the study period from June 2012 to October 2013. A total of 132 residents of Tuen Mun District reported syndromic markers at the individual and household levels on a weekly basis. Temporal patterns of these markers were compared with data derived from laboratory surveillance by dynamic linear regression. Household respiratory symptoms were found to be an effective syndromic marker, pre-dating overall laboratory virus surveillance results on influenza diseases in two influenza seasons by 3-4 weeks. To conclude, respiratory symptoms can be a good marker predicting the onset of the influenza season in the community, and is particularly useful with regard to data from households, even if the sample size may not be a large one.

Effectiveness and cost-effectiveness of a group-based pain self-management intervention for patients undergoing total hip replacement: feasibility study for a randomised controlled trial

Total hip replacement (THR) is a common elective surgical procedure and can be effective for reducing chronic pain. However, waiting times for THR can be considerable, and patients often experience significant pain during this time. A pain self-management intervention may provide patients with the skills to enable them to manage their pain and its impact more effectively before surgery. However, studies of arthritis self-management programmes have faced challenges because of low recruitment rates, poor intervention uptake, and high attrition rates. This study aimed to evaluate the feasibility of a randomised controlled trial (RCT) to assess the effectiveness and cost-effectiveness of a group-based pain self-management course for patients undergoing THR. Specific objectives were to assess trial design, ascertain recruitment and retention rates, identify barriers to participation, refine data collection methods, and evaluate uptake and patient satisfaction with the course. Patients listed for THR in an elective orthopaedic centre Bristol, UK were sent a postal invitation about the study. Participants were randomised to attend a pain self-management course plus standard care or standard care only using a computer-generated randomisation system. The pain self-management course was delivered by Arthritis Care and consisted of two half-day group sessions prior to surgery and one full-day group session 2–4 months after surgery. A structured course evaluation questionnaire was completed by participants. Outcomes assessment was by postal questionnaire prior to surgery and 1-month, 3-months and 6-months after surgery. Self-report resource use data were collected using a diary prior to surgery and inclusion of resource use questions in the 3-month and 6-month post-operative questionnaires. Brief telephone interviews were conducted with non-participants to explore barriers to participation. Postal invitations were sent to 385 eligible patients and 88 patients consented to participate (23% recruitment rate). Participants had a mean age of 66 years and 65% were female. Brief interviews with 57 non-participants revealed the most common reasons for non-participation were perceptions about the intervention and difficulties in getting to the hospital for the course. Of the 43 patients randomised to the intervention group, 28 attended the pre-operative pain self-management sessions and 11 attended the post-operative sessions. Participant satisfaction with the course was high, and patients enjoyed the group format. Retention of participants was acceptable, with 83% completing follow-up. Questionnaire return rates were high (76–93%), with the exception of the pre-operative resource use diary (35%). Completion rates for the resource use questions varied by category and allowed for an economic perspective from the health and social care payer to be taken. Undertaking feasibility work for a RCT is labour-intensive; however this study highlights the importance of conducting such work. Postal recruitment resulted in a low recruitment rate and brief interviews with non-participants provided valuable information on barriers to participation. Embedding collection of resource use data within questionnaires resulted in higher completion rates than using resource use diaries. While patients who attended the course gave positive feedback, attendance was low. Findings from this feasibility study enable us to design successful definitive group-based RCTs in the future.

Patient recruitment and experiences in a randomised trial of supervised exercise training for individuals with abdominal aortic aneurysm

We sought to describe patient recruitment and experiences in a randomised controlled trial of a 12-week (thrice weekly) supervised exercise program for patients with small abdominal aortic aneurysm (AAA). Potential patients were identified via AAA surveillance lists and vascular clinics and invited to participate in the study. Upon completion of baseline assessments, patients were randomly allocated 1:1 to exercise or usual care. Patients completing the exercise arm were invited to attend a focus group session to explore experiences of diagnosis, management of condition, trial recruitment, and expectations and experiences of the exercise program. Between January 2010 and September 2011, 545 patients were identified. The response rate to postal invitation was 81.7% (445/545), with 108 patients responding as "interested." Only 28 of these patients were eligible and recruited (46.7% of recruitment target), yielding an overall recruitment rate of 5.1%. However, the estimated recruitment rate among eligible patients was 23.7%. Twenty-five patients (89.3%) completed the study, and compliance to the exercise program was 94%. Participants attending the focus group session indicated that the exercise program was manageable, beneficial, and enjoyable. The feasibility of supervised exercise training in individuals with small AAA remains unclear. Our study revealed a poorer than expected recruitment rate, but good compliance to, and feedback for, the exercise intervention. We present potential explanations for these findings and suggestions for future trials involving similar populations.

Use of research questionnaires in the NHS Bowel Cancer Screening Programme in England: impact on screening uptake

The NHS Bowel Cancer Screening Programme in England offers biennial screening to those aged 60-74 using a faecal occult blood test (FOBt) sent by post. Data from this national clinical programme can also be used for research. Awareness of the impact of such studies on screening participation is important. To investigate the effect on screening uptake of adding a research questionnaire to the postal screening invitation. People invited for screening in 2008-10 in two areas of England were randomized to receive or not to receive an additional research study questionnaire, consent form and study information, either with their test kit or 2-3 days later. Uptake of screening was examined in relation to study mailings. Among 11,579 people invited for screening by the Midlands and North West Bowel Cancer Screening Hub, screening uptake was significantly lower in those who received study documents with their FOBt kit than in those who did not (48.6% vs 53.5% respectively: p < 0.001). The reduction in uptake was similar in men and women, and was greater in people living in more deprived areas. Among a further 36,195 people invited for screening by the Midlands and North West and Southern Hubs, sending study documents by separate mailing 2-3 days after the FOBt kit did not affect screening uptake (uptake with and without additional study mailing: Midlands and North West, 56.7% and 56.2% respectively, p = 0.6; Southern, 52.0% and 51.4% respectively, p = 0.5). Researchers planning studies that include contact with potential participants within the NHS Bowel Cancer and similar screening programmes should be aware of the potential impact on uptake.

Attitudes and practices in the management of ADHD among healthcare professionals who responded to a European survey.

To examine attitudes and practices in the management of attention-deficit/hyperactivity disorder (ADHD) among health professionals across seven European countries. The web-based survey was developed by an international steering committee of ADHD experts and consisted of 64 multiple-choice questions relating to ADHD, covering the following topics: attitudes, diagnosis, referral, treatment and improving care. Health professionals working with ADHD were identified using a medical marketing database (Medical Marketing Service Inc., IL, USA) and invited via email to participate in the survey. No incentive was offered for participation and the survey was only available in English. Over 22 000 emails and postal invitations were sent. One hundred and thirty-four (0.6%) health professionals completed the survey. Results highlighted significant differences by profession and country. In general, ADHD is considered a clinically important and valid disorder (n = 111, 84%), with biological underpinnings (n = 82, 62%), continuing into adulthood (n = 123, 93%) and responsive to treatment. Respondents from France were less likely to be convinced about biological validity (n = 4, 27%) and those from Italy and France were more likely to be concerned about the risk of underdiagnosis (n = 9, 64% and n = 9, 60%, respectively). Psychologists were the specialty who most frequently reported not believing in the diagnostic validity of ADHD (n = 4, 19%). One-third (n = 25, 35%) of respondents recommended medical tests before prescribing medication, with differences emerging by country despite the lack of support for such routine assessments in the guidelines. Despite the very low response rate, intriguing country- and profession-specific differences emerged in this study and warrant further exploration.

Understanding of and attitudes to genetic testing for inherited retinal disease: a patient perspective

Background/aimsThe views of people with inherited retinal disease are important to help develop health policy and plan services. This study aimed to record levels of understanding of and attitudes to...

Using Mixed-Mode Contacts in Client Surveys: Getting More Bang for Your Buck

Surveys are commonly used in Extension to identify client needs or evaluate program outcomes. This article examines how available email addresses can be incorporated into mixed-mode procedures for surveys. When mail and email addresses are used to implement a sequence of email and postal invitations in a mixed-mode survey, response rates were somewhat lower than those for mail only surveys. Item nonresponse is, however, lower for questionnaires completed via the Web, and costs for postage were substantially lower for the mixed-mode groups (because 60% of the surveys were completed via the Web). The study demonstrates the benefit of using mixed-mode surveys.

Prevalence of the chronic prostatitis/chronic pelvic pain syndrome among 40–69-year-old men residing in a temperate climate

Objective. The aim of this study was to describe the prevalence of the chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) among middle-aged men in a region with a temperate climate, i.e. a community in western Sweden. Material and methods. Men aged 40–69 years who, on the basis of postal invitation, volunteered to participate in a study regarding erectile dysfunction as a risk factor for cardiovascular disease, were asked also to complete the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI). Results. In total, 459 of 900 men responded to the invitation. CP/CPPS-like symptoms, i.e. perineal and/or ejaculatory pain and an NIH-CPSI pain score of 4 or greater, were reported by 23 men (5%). More severe symptoms, with a pain score of at least 8 and perineal and/or ejaculatory pain, were reported by 15 men (3.3%). Conclusions. In this cross-sectional population-based study 5% had NIH-CPSI scores suggestive of CP/CPPS, which is in the lower range compared with studies from other regions, refuting the idea that CP/CPPS should be more common in regions with a temperate climate.

Irrigation protocol among endodontic faculty and post-graduate students in dental colleges of India: A survey

Background:Irrigation protocol is the most critical step during the disinfection of an infected root canal system.Aim:The purpose of this study was to determine the root canal irrigation trends being practiced among the endodontic teaching faculty and post-graduate students in the dental colleges present in India.Materials and Methods:A postal invitation to participate in this national survey was sent to the Department of Conservative Dentistry and Endodontic of 294 Dental Colleges present in India. A total of 2389 forms were successfully delivered out of which 794 duly filled forms were received back. Survey participants were asked about their irrigant selection, irrigant concentration, smear layer removal protocol, and use of adjuncts during irrigation.Results:This survey elicited a positive response rate of 33.23%. Our data indicated that 92.8% of respondents use sodium hypochlorite (NaOCl) as the primary endodontic irrigant, with 26 gauge needle being most preferred for syringe irrigation, with 49.3% of them using it at a concentration of 2.6-4.0%. 68% of our respondents aim to remove the smear layer during the endodontic treatment while 47% reported using ultrasonic activation as an adjunct during their irrigation protocol.Conclusions:The findings of this survey are that the majority of teaching institutions in India are employing NaOCl (2.6-4.0%) as the primary endodontic irrigant. The concept of smear layer removal is high (68%), and there is a general trend (78%) to modify the irrigation protocol according to the status of the pulp, status of the periapex and in retreatment cases.

Combining Mail and E-Mail Contacts to Facilitate Participation in Mixed-Mode Surveys

This study examines how available e-mail addresses can be incorporated into mixed-mode procedures for surveys of the public, especially client groups. Cooperative Extension Service clients provide the basis for analyzing how implementation procedures affect response rates and substantive findings. These clients form three strata based on contact information provided: postal address only, e-mail only, and both. From clients who provided mail and e-mail addresses, four experimental groups were created, including two mixed-mode groups, a mail-only group and an e-mail-only group. Using mail and e-mail addresses to implement a sequence of e-mail and postal invitations in a mixed-mode design resulted in response rates that are equivalent to those for mail-only surveys. Also, clients who provided a postal address only differed on some attributes from those in the other strata. This study demonstrates the benefit of obtaining e-mail addresses and using them in mixed-mode surveys.

The psychosocial impact of chronic wounds on patients with severe epidermolysis bullosa

To explore the lived experience of individuals with chronic wounds associated with dystrophic and junctional epidermolysis bullosa (EB),to improve understanding and, therefore, enhance the care provided to this group of patients by acquiring in depth data on the psychosocial issues that affect them. A phenomenological study using interpretive phenomenological analysis was employed. A purposive sampling method was used with six individuals replying to postal invitation to participate. Following one-to-one interviews, six superordinate themes were identified. These were: coping, pain, perceptions, emotional impact, social impact and support network, each with subordinate themes. All of the superordinate themes have been identified by previous research into chronic wounds, burns and disfiguring conditions; however, new subordinate themes arose. This study highlighted the need for individuals with EB to have a multidisciplinary approach to their care with a particular need for pain management, psychological intervention and nursing support from those whom clients perceive as understanding the requirements of patients with EB. Further research into identity issues in individuals with EB is advocated. There were no external sources of funding for this study.The authors have no conflicts of interest to declare.

The associations between maternal pre-pregnancy body mass index or gestational weight change during pregnancy and body mass index of the child at 3 years of age

To estimate the associations between maternal pre-pregnancy body mass index (BMI) or gestational weight change (GWC) during pregnancy and offspring BMI at 3 years of age, while taking several pre-and postnatal factors into account. The Norwegian Mother and Child Cohort Study is a population-based pregnancy cohort study of women recruited from all geographical areas of Norway. The study includes 31 169 women enrolled between 2000 and 2009 through a postal invitation sent to women at 17-18 weeks of gestation. Data collected from 5898 of the fathers were included. MAIN OUTCOME MESURES: Offspring BMI at 3 years was the main outcome measured in this study. Mean maternal pre-pregnancy BMI was 24.0 kg m(-2) (s.d. 4.1), mean GWC in the first 30 weeks of gestation was 9.0 kg (s.d. 4.1) and mean offspring BMI at 3 years of age was 16.1 kg m(-2) (s.d. 1.5). Both maternal pre-pregnancy BMI and GWC were positively associated with mean offspring BMI at 3 years of age. Pre-pregnancy BMI and GWC also interacted, and the strength of the interaction between these two factors was strongly associated with the increase in offspring BMI among mothers who gained the most weight during pregnancy and had the highest pre-pregnancy BMI. Our findings show that results could be biased by not including pre-pregnant paternal BMI. This large population-based study showed that both maternal pre-pregnancy BMI and GWC were positively associated with mean offspring BMI at 3 years of age.