Aims: To examine whether observed changes in self-reported psychological distress symptoms reflect true changes in psychological distress in the population, or more specifically, to present statistical methods to check for nonresponse bias and demographic changes. Methods: Lack of representativity, nonresponse bias and demographic changes were controlled for by weighing of data (sample-balancing or raking). Results: Controlling for age, gender and education, or holding the demographic structure constant over time, slightly weakened the decrease in psychological distress from 1998 to 2002, and left the changes in psychological distress from 2002 to 2008 almost unchanged. When the level of psychological distress was held constant across years in every subgroup defined by age, gender and education, in order to isolate the effects of changes in demography, the distress scores showed only minor variation across data collection occasions from 1998 to 2008. Conclusions: The observed modest decrease in psychological distress from 1998 to 2002 may partly be explained by selection and demographic changes, while this is not the case with the more pronounced changes from 2002 to 2008.
KesslerRCÜstünTB. The WHO world mental health survey: global perspectives on the epidemiology of mental health disorders. Cambridge, UK: Cambridge University Press, 2009.
2.
KringlenETorgersenSCramerV. A Norwegian psychiatric epidemiological study. Am J Psychiatry2001;158(7):1091–8.
3.
Socialstyrelsen. Folkhelsorapport. Epidemiologisk center, Stockholm, 2005.
4.
SandangerINygårdJFSørensenTDalgardOS. Return of the depressed men: changes in distribution of depression and symptom cases in Norway between 1990 and 2001. J Affective Disorders2007;100:153–62.
5.
NilssonEBogrenMMattissonCNettebladtP. Point prevalence of neurosis in the Lundby Study 1947–1997. Nord J Psychiatry2007;61:33–9.
6.
KesslerRCDemlerOFrankRGOlfsonMPincusHAWaltersEE. Prevalence and treatment of mental disorders, 1990 to 2003. New England J Med2005;52(24):2515–23.
7.
MurphyJMLairdNMMonsonRRSobolAMLeightonAH. A 40-year perspective on the prevalence of depression. Arch Gen Psychiatry2000;57:209–15.
8.
MurphyJMLairdNMMonsonRRSobolAMLeightonAH. A 40-year perspective on the prevalence of depression. Psychol Med2000;30(3):505–14.
9.
RobinsLNRegierDA. Psychiatric disorders in America: the epidemiologic catchment area study. Rockland, Maine: The Free Press, 1991.
10.
ComptonWMConwayKPStinsonFSGrantBF. Changes in the prevalence of major depression and comorbid substance use disorders in the United States between 1991–1992 and 2001–2002. Am J Psychiatry2006;163:2141–7.
11.
RahmquistMCarstensenJ. Trend of psychological distress in a Swedish population from 1989 to 1995. Scand J Soc Med1998;26(3):214–22.
12.
SalomonJANordhagenSOzaSMurrayCJL. Are Americans feeling less healthy? The puzzle of trends in self-rated health. Am J Epidemiol2009;170(3):343–51.
13.
HaggardLM. Health surveys and social science: a primer for applied survey projects. Salt Lake City, Utah: Bureau of Surveillance and Analysis, Utah Department of Health, 1998.
14.
TolonenH. Towards the high quality of population health surveys standardization and quality control. Helsinki: National Public Health Institute, 2005.
15.
NygårdJFKlungsøyrOSandangerISvenssonE. Selection effects in psychiatric epidemiology – a 14 year prospective study of the Hopkins Symptom Check List-25 as a predictor of mortality in the Norwegian general population. Soc Psychiatry Psychiatr Epidemiol2009;44:881–6.
16.
HansenVJacobsenBKArnesenE. Prevalence of serious psychiatric morbidity in attenders and non-attenders to a health survey of a general population: the Tromsoe health study. Am J Epidemiol2001;154(10):891–4.
17.
YanovitzkyIZanuttoEHornikR. Estimating causal effects of public health education campaigns using propensity score methodology. Evaluation and Program Planning2005;28:209–20.
18.
LevyPSLemeshowS. Nonresponse in sample surveys. In: EverittBSHowellsDC (Eds) Encyclopedia of statistics in behavioral science. Chichester, England: John Wiley & Sons2005, Vol. 3, pp 1433–6.
BjellandI. Anxiety and depression in the general population – issues related to assessment, comorbidity and risk factors. Dr dissertation, University of Bergen, Bergen, 2004.
21.
DerogatisLRLipmanRSRickelsKUhlenhuthEHCoviL. The Hopkins Symptom Checklist (HSCL) – a self-report symptom inventory. Behavioral Sci1974;19(1):1–15.
22.
StrandBHDalgardOSTambsKRognerudM. Measuring the mental health status of the Norwegian population: a comparison of the instruments SCL-25, SCL-10, SCL-5 and MHI-5 (SF-36). Nord J Psychiatry2003;57(2):1–6.
23.
SandangerIMoumTIngebrigtsenGDalgardOSSørensenTBruusgaardD. Concordance between symptom screening and diagnostic procedure: the Hopkins Symptom Checklist-25 and the composite international diagnostic interview I. Soc Psychiatry Psychiatr Epidemiol1998;33:345–54.
24.
SandangerI. Occurrence of psychiatric disorders - an epidemiological study, conceptual, methodological, and empirical issues. Oslo: Institute of general practice and community medicine, University of Oslo and Institute group of psychiatry, University of Oslo, 1999.
25.
DalgardOSStrømseng SjetneIAndresen BjærtnesØHelgelandJ. Levekårsundersøkelsen 2005 – Psykiske problemer og behandling. Folkehelseinstituttet Rapport 2008: 5 (in Norwegian). Oslo: Norwegian Institute of Public Health.
26.
GjesdalSHaugKRingdalPRVollsetSEMaelandJG. Risiko for uforepensjonering blant unge langtidssykmeldte. Tidsskrift for Den Norske Laegeforening2005;125(13): 1801–5.
Sosial og Helsedepartementet (1997–1998): St.Prop.63 (1997–2006). Om opptrappingsplanen for psykisk helse 1999–2006. Endringer i statsbudsjettet for 1998 (in Norwegian; Ministry of Health and Social Affairs, Parl. No 63, The escalation plan for mental health 1999–2006, changes in the state budget for 1998).
29.
Sosial og Helsedirektoratet. Opptrappingsplanen for psykisk helse 1999–2006. Status 2003. Report IS-1127 (in Norwegian; Norwegian Directory of Health and Social Affairs; the escalation plan for mental health 1999–2006).
30.
JohansenRRognerudMSundetJM. Levekårsundersøkelsene 1998, 2002 og 2005 – Utvikling i psykisk helse. Report from The Norwegian Institute of Public Health 2008: 4. Oslo: Norwegian Institute of Public Health (in Norwegian).
