Epidemiology of HCV infection among drug users (DUs) has been widely studied. Prevalence and sociobehavioural data among DUs are therefore available in most countries but no study has taken into ...account in the sampling weights one important aspect of the way of life of DUs, namely that they can use one or more specialized services during the study period. In 2004-2005, we conducted a national seroepidemiologic survey of DUs, based on a random sampling design using the Generalised Weight Share Method (GWSM) and on blood testing.
A cross-sectional multicenter survey was done among DUs having injected or snorted drugs at least once in their life. We conducted a two stage random survey of DUs selected to represent the diversity of drug use. The fact that DUs can use more than one structure during the study period has an impact on their inclusion probabilities. To calculate a correct sampling weight, we used the GWSM. A sociobehavioral questionnaire was administered by interviewers. Selected DUs were asked to self-collect a fingerprick blood sample on blotting paper.
Of all DUs selected, 1462 (75%) accepted to participate. HCV seroprevalence was 59.8% 95% CI: 50.7-68.3. Of DUs under 30 years, 28% were HCV seropositive. Of HCV-infected DUs, 27% were unaware of their status. In the month prior to interview, 13% of DUs shared a syringe, 38% other injection parapharnelia and 81% shared a crack pipe. In multivariate analysis, factors independently associated with HCV seropositivity were age over 30, HIV seropositivity, having ever injected drugs, opiate substitution treatment (OST), crack use, and precarious housing.
This is the first time that blood testing combined to GWSM is applied to a DUs population, which improve the estimate of HCV prevalence. HCV seroprevalence is high, indeed by the youngest DUs. And a large proportion of DUs are not aware of their status. Our multivariate analysis identifies risk factors such as crack consumption and unstable housing.
Since the mid-1990s, Time-Location Sampling methods have been widely used in France in quantitative research about the homeless (Marpsat and Firdion, 2000; Brousse, 2002) and drug users (Emmanuelli ...et al. 2003; Jauffret-Roustide et al. 2006). Adapted from methods of indirect sampling initially developed in the United States (Burt and Cohen, 1989; Dennis and Iachan, 1993), they enable the design of representative samples of hard-to-reach populations for whom there are no sample frames, by basing it on support facilities for the populations of interest: day centres, soup kitchens, accommodation services, health care, mobile teams etc. However, in transition from the theoretical protocol to its implementation, various difficulties emerge. In particular, the necessary involvement of these support services; the constraints associated with the administering of questionnaires in sometimes very particular conditions (at night, in public places or while following mobile teams) and the singular organisation of each of the services that has to be involved means that challenges occur as regards coverage of the field being investigated and the representativeness of the sample. These challenges mean that the method has to be appropriately and pragmatically adapted to the various configurations that are met with. In this perspective, we will show how the integration of qualitative methods, such as the observation of the services and the realisation of in-depth interviews with the persons in charge of them, have contributed, along the various data collections and with the accumulation of experiences, to improve the methodology of and the scope covered by quantitative surveys.
Depuis le milieu des années 1990, les méthodes d’échantillonnage espace-temps (ou Time-Location Sampling) ont été largement utilisées en France dans les recherches quantitatives auprès des ...populations sans domicile (Marpsat et Firdion, 2000; Brousse, 2002) et d'usagers de drogues (Emmanuelli et al. 2003; Jauffret-Roustide M. et al. 20061). Adaptées de méthodes d’échantillonnage indirect initialement développées aux Etats-Unis (Burt et Cohen, 1989; Dennis et Iachan, 1993), elles permettent de construire des échantillons représentatifs de populations difficiles à joindre, pour lesquelles il n'existe pas de base de sondage, en s'appuyant sur les dispositifs d'aide aux populations concernées: services d'accueil, de restauration, d'hébergement, de soins, équipes itinérantes… Toutefois, du protocole théorique à sa mise en œuvre pratique, diverses difficultés émergent. En particulier, la nécessaire implication de ces services d'aides, les contraintes associées à la passation de questionnaires dans des conditions parfois très particulières (de nuit, dans des espaces publics ou au sein d’équipes mobiles…), l'organisation singulière de chacun des services dans lesquels on est amené à enquêter, invitent à réfléchir aux enjeux de couverture du champ investigué mais aussi de représentativité de l’échantillon, et à adapter la méthode aux différentes configurations rencontrées. Dans cette perspective, nous montrerons comment l'intégration de méthodes d'enquêtes qualitatives, telles que l'observation des services et la réalisation d'entretiens auprès des responsables, a contribué, au fil des collectes et des expériences capitalisées, à améliorer la méthodologie et le champ couvert par les enquêtes quantitatives.
Knowledge dissemination is an emerging issue in population studies, both in terms of ethics and data quality. The challenge is especially important in long term follow-up surveys and it requires ...methodological imagination when the population is illiterate. The paper presents the dissemination project developed in a demographic surveillance system implemented in rural Mali over the last 20 years. After basic experience of document transfer, the feedback strategy was developed through audiovisual shows and theatre sketches. The advantages and drawbacks of these media are discussed, in terms of scientific communication and the construction of dialogue with the target population.
Constructing a survey over time Hertrich, Véronique; Lesclingand, Marie; Quaglia, Martine ...
Demographic research,
07/2011, Volume:
25
Journal Article
Peer reviewed
Open access
Knowledge dissemination is an emerging issue in population studies, both in terms of ethics and data quality. The challenge is especially important in long term follow-up surveys and it requires ...methodological imagination when the population is illiterate. The paper presents the dissemination project developed in a demographic surveillance system implemented in rural Mali over the last 20 years. After basic experience of document transfer, the feedback strategy was developed through audiovisual shows and theatre sketches. The advantages and drawbacks of these media are discussed, in terms of scientific communication and the construction of dialogue with the target population.
Knowledge dissemination is an emerging issue in population studies, both in terms of ethics and data quality. The challenge is especially important in long term follow-up surveys and it requires ...methodological imagination when the population is illiterate. The paper presents the dissemination project developed in a demographic surveillance system implemented in rural Mali over the last 20 years. After basic experience of document transfer, the feedback strategy was developed through audiovisual shows and theatre sketches. The advantages and drawbacks of these media are discussed, in terms of scientific communication and the construction of dialogue with the target population.
Challenges in Cross‐National Data Collection Pennell, Beth‐Ellen; Harkness, Janet A; Levenstein, Rachel ...
Survey Methods in Multinational, Multiregional, and Multicultural Contexts,
04/2010
Book Chapter
Abstract We analysed data from 49 cancer registries in 18 European countries over the period 1988–1999 to delineate time trends in cancer survival. Survival increased in Europe over the study period ...for all cancer sites that were considered. There were major survival increases in 5 year age-adjusted relative survival for prostate (from 58% to 79%), colon and rectum (from 48% to 54% men and women), and breast (from 74% to 83%). Improvements were also significant for stomach (from 22% to 24%), male larynx (from 62% to 64%), skin melanoma (from 78% to 83%), Hodgkin disease (from 77% to 83%), non-Hodgkin lymphoma (from 49% to 56%), leukaemias (from 37% to 42%), and for all cancers combined (from 34% to 39% in men, and from 52% to 59% in women). Survival did not change significantly for female larynx, lung, cervix or ovary. The largest increases in survival typically occurred in countries with the lowest survival, and contributed to the overall reduction of survival disparities across Europe over the study period. Differences in the extent of PSA testing and mammographic screening, and increasing use of colonscopy and faecal blood testing together with improving cancer care are probably the major underlying reasons for the improvements in survival for cancers of prostate, breast, colon and rectum. The marked survival improvements in countries with poor survival may indicate that these countries have made efforts to adopt the new diagnostic procedures and the standardised therapeutic protocols in use in more affluent countries.
We present estimates of population‐based 5‐year relative survival for adult Europeans diagnosed with central nervous system tumors, by morphology (14 categories based on cell lineage and malignancy ...grade), sex, age at diagnosis and region (UK and Ireland, Northern, Central, Eastern and Southern Europe) for the most recent period with available data (2000–2002). Sources were 39 EUROCARE cancer registries with continuous data from 1996 to 2002. Survival time trends (1988 to 2002) were estimated from 24 cancer registries with continuous data from 1988. Overall 5‐year relative survival was 85.0% for benign, 19.9% for malignant tumors. Benign tumor survival ranged from 90.6% (Northern Europe) to 77.4% (UK and Ireland); for malignant tumors the range was 25.1% (Northern Europe) to 15.6% (UK and Ireland). Survival decreased with age at diagnosis and was slightly better for women (malignant tumors only). For glial tumors, survival varied from 83.5% (ependymoma and choroid plexus) to 2.7% (glioblastoma); and for non‐glioma tumors from 96.5% (neurinoma) to 44.9% (primitive neuroectoderm tumor/medulloblastoma). Survival differences between regions narrowed after adjustment for morphology and age, and were mainly attributable to differences in morphology mix; however UK and Ireland and Eastern Europe patients still had 40% and 30% higher excess risk of death, respectively, than Northern Europe patients (reference). Survival for benign tumors increased from 69.3% (1988–1990) to 77.1% (2000–2002); but survival for malignant tumors did not improve indicating no useful advances in treatment over the 14‐year study period, notwithstanding major improvement in the diagnosis and treatment of other solid cancers.
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