The NSW CLEAR case-control study collects lifestyle and demographic information as well as biospecimens from people with cancer and controls in New South Wales, Australia. It has recruited over 9,400 participants since 2006, with the majority recruited through targeted identification of cancer patients. The most common cancer types are breast, prostate, colorectal, melanoma, and lung cancer. CLEAR is a valuable resource for cancer researchers, with the potential to advance understanding of cancer causes and outcomes.

1. The NSW Cancer,
Lifestyle and Evaluation
of Risk Study (CLEAR)
A resource for cancer research
Sitas F1,2,3, Nair-Shalliker V1, Revius M1, Christou C1, Yap S1, Armstrong K1, Salagame U1,2, Christian K1, Cottrill A4, Delaney G5, Kaadan N5, Thompson
J6, Haydu L6, Sara T7, Banks E8, Barton M9, Canfell K1,3, O’Connell D1,2,3,10.
1. Cancer Research Division, Cancer Council NSW. 2. University of Sydney. 3. University of NSW. 4. Hospitals Contribution Fund of Australia Ltd. 5. South Western Sydney and Sydney
Local Health District Clinical Cancer Registry. 6. Melanoma Institute Australia. 7. Southeastern Sydney and Illawarra Shoalhaven Local Health District Clinical Cancer Registry. 8. National
Centre for Epidemiology and Population Health, Australian National University. 9. Ingham Institute for Applied Medical Research, Liverpool Hospital. 10. University of Newcastle
Background
The NSW CLEAR case-control study commenced in 2006.
It collects lifestyle and demographic information as well as
biospecimens from people with all types of cancer and controls,
which are available as an open resource for researchers.
Methods
Population: NSW residents aged > 18 years.
Cases: People with any incident cancer.
Controls: Partners of cases, who are cancer free.
Study requirement: Consent to participate, completion of
questionnaire and an optional contribution of a blood specimen.
Study procedure
• Potential participants were approached using two methods:
i. In a targeted approach all people with a recent cancer diagnosis were
identified using a medical database, from the South Eastern Sydney
and Illawarra Shoalhaven Local Health District Clinical Cancer Registry
(SESAHS), Hospitals Contribution Fund of Australia (HCF), South
Western Sydney and Sydney Local Health District Clinical Cancer
Registry (SSWAHS), and Melanoma Institute Australia (MIA).
ii. In non-targeted approaches potential participants opt to participate in
the study after hearing of CLEAR through community based events.
• Blood specimens were processed at CCNSW Biobank Facility.
Figure 1. The relationship between cases and controls at the
recruitment phase is unlinked during analysis, resulting
in a pool of sex-matched, cancer-free controls
ANALYSIS
RECRUITMENT
CASE
CONTROL
Female
Male
Male
Female
Female
Female
Male
Male
Table 2. Most common cancer sites in CLEAR
Cancer Type
Breast
Prostate
Colorectal*
Melanoma
Lung
Non Hodgkin Lymphoma
Thyroid
Ovary
Bladder
* Colorectal cancers include C18-C20
Risk factor Cancer type
Lung cancer
Results
• CLEAR has recruited 9433 participants (7373 cases and 2060 controls)
and 72% of these participants have contributed a blood specimen. The
response rate for all targeted sites is approximately 20% (Table 1).
Table 1. Participation characteristics in each targeted recruitment site
Median age (Min, Max)
Total mailouts
SESAHS
SSWAHS
HCF
MIA
All sites
COMBINED
Cancer Group
Urogenital
Bowel†
Lymphohaematopoietic
Skin
Gynaecological
Respiratory
Head and Neck
Upper GI
Thyroid / Endocrine
n
1218
807
484
483
337
275
201
177
152
%
21
14
8
8
6
5
3
3
3
†Bowel cancers include C18-C21
Table 3. Odds ratios for smoking and tobacco related cancers in CLEAR and
international studies
Smoking
Mailouts
%
26
16
13
8
4
4
2
2
2
• The most common cancer types in CLEAR are listed in Table 2.
• Positive predictive values for self report of the top five cancers
compared to linkage with NSWCCR are > 95%.
• The risk of lung cancer in current smokers in both men and women,
after adjusting for age, socioeconomic status and migrant status were
similar to those from other contemporary studies in the UK and USA
(Table 3).
Record linkage
• Annual linkage with the NSW Central Cancer Registry (NSWCCR) is
undertaken to validate self reported cancer status, and to obtain stage of
disease.
• Other potential linkages include hospital admissions and Medicare claims.
Recruitment
Site
n
1533
976
791
458
255
227
145
129
94
Response rate %1
Case
Control
14697
14606
9453
1873
25
14
19
28
61 (18, 80)
60 (18, 93)
62 (21, 90)
60 (19, 92)
60 (22, 86)
59 (22, 92)
63 (33, 93)
59 (28, 86)
40629
20
61 (18, 93)
Tobacco related
cancers
Study
Variable
CLEAR*
Never
Past
Current†
Cancer Prevention Study1** Never
Past
Current††
Million Women Study2***
Never
Past
Current
CLEAR*
Never
Past
Current†
JCCC3****
Never
Past
Current†
OR (95% CI)
1.0
5.1
20.9
1.0
8.1
23.4
1.0
21.4
1.0
1.4
2.2
1.0
1.4
1.9
Women
(3.1, 8.3)
(12.0, 36.3)
(7.2, 9.1)
(19.6, 25.6)
(19.7, 23.2)
(1.0, 2.1)
(1.5, 3.4)
(1.1, 1.8)
(1.6, 2.2)
1.0
5.8
31.7
1.0
7.1
25.6
1.0
1.4
4.9
1.0
2.8
4.6
• Approximately 80% of all CLEAR participants are
recruited from sites with a targeted approach.
(2.9, 11.7)
(14.9, 67.7)
(6.1, 8.2)
(21.7, 30.3)
(1.0, 1.9)
(3.5, 7.0)
(2.2, 3.5)
(3.7, 5.7)
* adjusted for age, socioeconomic status and migrant status
** adjusted for cohort, age, race and education level
***adjusted for recruitment site, age, body mass index, socioeconomic status, current alcohol intake, physical activity, oral contraceptive use, menopausal
status and hormone therapy use.
**** adjusted for age, education, smoking status and cooking fuel
† current smokers are classified as those who still smoke or those who had quit smoking within the previous five years from date of recruitment into study
† † current smokers are classified as those who were still smoking at time of recruitment into study
61 (22, 93)
1 Response rate (%) = Number of consents received/total mail out sent for each site
Men
Conclusions
CLEAR is a valuable resource for cancer researchers interested in the causes
and consequences of a cancer diagnosis. It has the potential to significantly
advance our knowledge in the occurrence and outcome of various cancers.
References
1. Thun M et al NEJM. 2013;doi:10.1056/NEJM
sa 1211127
2. Pirie et al Lancet. 2013; doi: 10.1016/S01406736(12):61720-6
3. Stein et al British Journal of Cancer. 2008;
98:1586 – 1592
Funding
The NSW CLEAR Study is
funded by Cancer Council NSW
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CLEAR Study
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