DON'T CHANGE PRICE AFTER AGREEING TO ORIGINAL!
Public Health Article Critique: AIR QUALITY
400 WORDS APA FORMAT MIN 3 REFERENCES
Sahlberg B et al. (2010). Sick building syndrome in relation to domestic exposure in Sweden–a cohort study from 1991 to 2001. Scandinavian Journal of Public Health. 38(3): 232-8. (ARTICLE ATTACHED)
What do you think the public health significance of the research question in this study was? Is it mostly of local significance or is there a global impact? Explain. Does the study fill an important gap, in your opinion? Why or why not? Critique the methodology. Why do you think the authors chose this methodology and what would you have done differently? Explain. Interpret the results in your own words and then discuss with your colleagues whether you agree or disagree with the author’s interpretations and why.
Scandinavian Journal of Public Health, 2010; 38: 232–238
Sick building syndrome in relation to domestic exposure in Sweden – A
cohort study from 1991 to 2001
B. SAHLBERG, G. WIESLANDER & D. NORBÄCK
Department of Occupational and Environmental Medicine, Uppsala University Hospital and Uppsala University, Sweden
Abstract Background: Most studies on sick building syndrome (SBS) are cross-sectional and have dealt with symptoms among office workers. There are very few longitudinal cohort studies and few studies on SBS in relation to domestic exposures. The aim of this study was to investigate changes in SBS symptoms during the follow-up period and also to investigate changes in different types of indoor exposures at home and relate them to SBS symptoms in a population sample of adults from Sweden. We also wanted to investigate if there was any seasonal or regional variation in associations between exposure and SBS. Methods: A random sample of 1,000 people of the general population in Sweden (1991) was sent a self administered questionnaire. A follow-up questionnaire was sent in 2001. Results: An increased risk for onset of any skin symptoms (risk ratio (RR) 2.32, 1.37–3.93), mucosal symptoms (RR 3.17, 1.69–5.95) or general symptoms (RR 2.18, 1.29–3.70) was found for those who had dampness or moulds in the dwelling during follow-up. In addition people living in damp dwellings had a lower remission of general symptoms and skin symptoms. Conclusions: Dampness in the dwelling is a risk factor for new onset of SBS symptoms. Focus on indoor environment improvements in dwellings can be beneficial both for the inhabitants and the general population. Reducing dampness in buildings is an important factor for reducing SBS symptoms in the general population.
Key Words: Asthma, building dampness, cohort study moulds, indoor environment, sick building syndrome (SBS)
Sick building syndrome (SBS) is a set of non-specific
symptoms occurring in a particular building and the
symptoms normally improve or disappear when
people are away from the building. Such non-specific
symptoms are common in the general population 
and even more common among people living in
buildings with indoor air problems. The syndrome
has been defined empirically on the basis of case
reports in which the occupants of a specific building
described similar symptoms that were attributed to
indoor climate problems . Various factors, such as
wall-to-wall carpeting, type of ventilation system,
high room temperature, low supply of outdoor air,
and low air humidity have been shown to influence
the prevalence of SBS symptoms [3–5]. Female
gender and history of allergic disorder have been
shown in many studies to be important risk factors
for SBS symptoms [3–6]. In buildings with a CO2 level <800 ppm the risk for SBS symptoms decreased  and SBS symptoms can be more common at
personal airflow rates below 10 l/s .
Building dampness is a common indoor exposure,
and has been shown to be related to an increased
prevalence of both asthmatic symptoms and SBS
[9–11]. In a review by Bornehag et al. (2001), it was
concluded that dampness in buildings is a risk factor
and there are associations between both self-reported
and observed dampness and symptoms . The
dampness approximately doubles the risk of health
effects [9,10]. Building dampness in Swedish multi-
family residential buildings has been reported to be
related to a pronounced increase of symptoms com-
patible with SBS symptoms .
One common indoor source of volatile organic
compounds (VOC) is emissions from fresh paint.
Correspondence: B Sahlberg, Department of Occupational and Environmental Medicine, Uppsala University Hospital and Uppsala University, SE-751 85
Uppsala, Sweden. Tel: þ46 186 113869. Fax: þ46 185 19978. E-mail: [email protected]
(Accepted 7 September 2009)
� 2010 the Nordic Societies of Public Health DOI: 10.1177/1403494809350517
Two recent studies have shown that 26%–32% of the
Swedish population have had the interior of their
dwelling painted during the last year [1,13].
Nowadays most indoor paint in Sweden is water
based  and emissions from fresh indoor paint in
the dwelling may cause airway symptoms  and
eye irritation [1,14]. In addition, tobacco smoking is
related to many diseases such as chronic obstructive
pulmonary disease (COPD), lung cancer and ischae-
mic heart disease . Some SBS symptoms,
e.g. general symptoms, are also related to tobacco
smoking  and some studies have shown that
exposure to environmental tobacco smoke (ETS)
contributes to the occurrence of SBS symptoms .
Most studies on SBS are cross-sectional and have
dealt with symptoms among office workers. There
are hardly any longitudinal cohort studies [18,19]
and few studies on SBS in relation to domestic
exposures [1,6,20–22]. Moreover only a few studies
deal with risk factors for SBS symptoms in the
general population [1,19]. To our knowledge there
are no longitudinal studies on SBS symptoms in
relation to home environmental factors. Since a
cross-sectional study does not give strong evidence
on causal relations, there is a need for longitudinal
studies on SBS, especially in the general population.
The aim of this study was to investigate changes of
SBS and different types of indoor exposures at home
over a 10-year follow-up period (1991–2001) in a
population sample of adults from Sweden. Moreover
we studied the onset of SBS in relation to personal
factors at baseline and home exposure during the
follow up. We also wanted to investigate if there was
any seasonal or regional variation between indoor
exposures and SBS symptoms.
Material and methods
The study population consisted of a random sam-
ple of 1,000 persons in the general population aged
20–65 years in 1991. The sampling was done by
Statistics Sweden, which is a central government
authority for official statistics and other government
statistics, and in this capacity also has the responsi-
bility for coordinating and supporting the Swedish
system for official statistics. In order to study sea-
sonal effects, the sample was further divided into
four sub-samples (250 subjects in each). The subjects
in each sub-sample received the standardized
self-administered questionnaire during one of the
four seasons (September 1991 to August 1992). The
response rate was 70%. A follow-up questionnaire
was sent after 10 years (September 2001 to August
2002) to all subjects who participated in the first
study (n¼695), following the same division into
seasonal sub-groups as in the first study. The
response rate in the follow-up was 61% (n¼427).
Assessment of symptoms and personal factors
The questionnaire contained questions on age, sex,
hay-fever and smoking habits. Current smokers were
defined as those participants in the interview who
reported smoking, smoking more than one cigarette
per day, and reported ceasing smoking less than a
year ago. The questionnaire contained questions
requiring ‘‘yes’’ or ‘‘no’’ answers on 16 different
SBS symptoms used in earlier investigations .
In Table I the SBS symptoms are listed. The recall
period was three months. Work-related symptoms
were not addressed in this study. There was one
question asking whether the symptoms disappeared
or improved when being away from the workplace or
the home environment. However, this information
was not used in this study, which covers symptoms
regardless of the subject’s opinion on causes.
The prevalence of symptoms was calculated for
each of the 16 symptoms. The symptoms were
classified as eye, nasal, throat, facial dermal, or
general symptoms, and the prevalence of subjects
with at least one symptom in each group was
calculated. The prevalence of subjects with at least
one mucous membrane symptom (eye irritation,
swollen eyelids, nasal obstruction, dryness in throat,
sore throat, or irritating cough), dermal symptoms or
general symptoms was calculated.
Assessment of information on the dwelling
The questionnaire requested information on building
age, type of building, type of ventilation system, air
humidification, presence of wall-to-wall carpets, and
four different signs of microbial growth, malodours
or building moisture during the last 12 months. The
questions on building dampness have been validated
in a previous study . The validation was made by
comparing self-reported building dampness by the
inhabitant in the dwelling, with observations on signs
of building dampness made by an occupational
hygienist visiting the dwellings. If the presence of at
least one observed sign of building dampness was
used as the gold standard, sensitivity was 74% and
specificity was 71%. The questionnaire used in the
follow up contained three additional questions on any
Sick building syndrome and domestic exposure: cohort study in Sweden 233
building dampness, any indoor painting, and any
wall-to-wall carpeting in any of the dwellings the
participants had lived in during the 10-year follow-up
period. These questions were used to study associa-
tions with onset of SBS.
Changes in prevalence of health parameters or
building characteristics were tested by the
McNemar test. For each person, the weekly occur-
rence of any mucosal, dermal or general symptom
was calculated both in the beginning and at the end of
the follow-up period. Onset of any mucosal symptom
was defined as presence of at least one mucosal
symptom at the end of the follow-up period, but
absence of any mucosal symptom in the beginning.
Onset of any dermal or any general symptom was
defined in a similar way. Remission of symptoms
was defined as presence of symptoms (mucosal,
dermal or general) in the beginning and absence of
the particular type of symptom at the end of the
follow up. Multivariate statistical analysis was per-
formed by multiple binominal regression, calculating
relative risk (RR) with 95% confidence interval (CI)
for onset or remission of each type of symptom
group. When studying onset of symptoms, partici-
pants with the particular type of symptoms at base-
line were excluded. When studying remission of
symptoms, only participants with the particular
symptom at baseline were included. In the binomial
models control was made for possible confounding
by keeping age at baseline, gender, current smoking
at baseline, and hay fever at baseline together with the
three home-exposure variables.
In addition, associations between dampness during
the follow-up and onset of symptoms was studied in
different sub-groups separately, stratifying for sex,
hay fever at baseline, smoking at baseline, region at
baseline (southern, mid and northern Sweden), and
the four seasons. In all statistical analyses, two-tailed
tests and a 5% level of significance was applied.
All analyses were done with SAS� system version 9.1.
The follow up study was restricted to those 427
people who participated in both the initial study and
the follow up-study. A comparison between partici-
pants (n¼427) and non-participants (n¼268) gave
the following results: the non-participants did not
differ significantly from the participants with respect
to age, gender, hay fever, doctor’s diagnosed asthma,
or smoking habits at baseline. The initial mean age
was 42 years. The prevalence of asthma had numer-
ically increased and the prevalence of hay fever
had significantly increased (Table I). There were
no significant changes in chronic bronchitis. The
prevalence of current smoking had decreased and the
prevalence of ex-smokers had increased significantly
(Table I). The prevalence of mucosal symptoms
remained unchanged, and any general and any skin
symptoms had decreased. Among individual symp-
toms cold and headache had decreased (Table I).
Some improvements in the home environment
with regard to building dampness and indoor moulds
were observed. Visible indoor mould during the last
year had decreased. Also, mouldy odour and any sign
of building dampness had decreased. Other types of
odour, excluding mouldy odour, had decreased. The
proportion of dwellings with mechanical ventilation
either in living rooms or bedrooms had slightly
increased (Table II). The prevalence of any type of
building dampness had increased, but water leakage,
Table I. The prevalence of asthma, allergies, chronic bronchitis,
smoking habits and type of symptoms among participants in both
(n¼427) p-value a
Asthma 7.8 9.7 0.18
Any type of allergy 27 27 1.00
Hay fever 12 16 0.04
Chronic bronchitis 6.9 6.2 0.56
Current smoker 28 19 0.002
Ex-smoker 22 32 <0.0001 Type of symptom
Eye irritation 16 19 0.27
Swollen eyelids 10 9 0.56
Nasal catarrh 12 11 0.61
Nasal obstruction 20 18 0.22
Dryness in the throat 18 17 0.46
Sore throat 8 6 0.08
Irritating cough 7 10 0.06
Any mucosal b
41 43 0.73
Headache 22 17 0.02
Tiredness 35 33 0.35
Sensation of getting a cold 23 16 0.0005
Nausea 6 7 0.32
Any general c
48 42 0.02
Facial itching 9 6 0.11
Facial rash 8 8 1.00
Itching on the hands 9 8 0.78
Rashes on the hands 10 8 0.18
Eczema 13 9 0.06
Any skin d
21 16 0.02
a Differences tested by McNemar statistical test.
b The prevalence
of subjects with at least one symptom classified as mucosal. c The
prevalence of subjects with at least one symptom classified as
general. d The prevalence of subjects with at least one symptom
classified as skin.
234 B. Sahlberg et al.
sign of floor dampness and visible moulds had
decreased during the study period. A large propor-
tion (70%) had painted indoors during the follow-up
period and nearly a third of these had used solvent-
based paints. Furthermore 31% of the subjects had
lived in a dwelling with wall-to-wall carpet and a third
had lived in a dwelling with some type of building
The cumulative incidence of subjects with new
onset of at least one symptom in each group was 12%
for skin symptoms, 28% for mucosal symptoms and
25% for general symptoms. For headache the cumu-
lative incidence was 10% and for tiredness it was
15%. An increased onset for any skin, mucosal or
general symptoms was found for those who had any
type of building dampness in the dwelling during
follow up. We did not find any relations between
onset of any symptoms and indoor painting, either
for any type of paint or for use of solvent-based
paints. Among personal factors hay fever at baseline
was related positively to onset of skin and mucosal
symptoms, and age was related to onset of mucosal
membrane symptoms (Table III). We also analyzed
the relationship between specific mucosal symptoms
such as eye, nose and throat and building factors and
personal factors. Onset of eye symptoms (RR 2.41,
1.38–4.35) and throat symptoms (RR 2.33, 1.10–
4.95) was significantly more common in damp
In the stratified analysis, we analyzed associations
between symptoms and dampness in the dwelling.
There was no consistent gender difference for the
association between onset of any type of symptoms
and dampness in the dwelling. Subjects with hay
fever had a numerically higher RR for onset of
general symptoms and skin symptoms, but confi-
dence intervals were overlapping. No regional or
seasonal differences for RR for onset of any symp-
toms in relation to dampness were observed.
Smokers at baseline had a consistently higher RR
for onset of general, skin and mucosal symptoms in
relation to dampness as compared to non smokers.
The RR was two to eight times higher for smokers,
but confidence intervals were partly overlapping.
Remission from general symptoms or skin symptoms
was less likely in subjects with dampness in the
dwelling, and remission from general symptoms was
less likely if the dwelling had been painted indoors
during follow up. Moreover, remission from skin
symptoms was less likely in subjects with hay fever at
baseline (Table IV).
The main findings in this study were that the
people who had any type of building dampness
had a significantly higher incidence for general
symptoms, skin symptoms and mucosal symptoms.
Table III. Relationship between onset of weekly symptoms, building factors and personal factors.
Type of symptoms
(RR 95% CI) b
(RR 95% CI) b
(RR 95% CI) b
Female gender 1.45 (0.96–2.21) 1.59 (0.88–2.89) 1.33 (0.88–2.02)
Age (10y) 0.90 (0.74–1.11) 1.11 (0.90–1.48) 1.11 (1.00–1.34)*
Hay fever 1.46 (0.78–2.73) 2.76 (1.30–5.84)* 2.30 (1.22–4.32)*
Current tobacco smoker 0.95 (0.57–1.59) 1.67 (0.86–3.21) 0.73 (0.44–1.22)
Any type of building dampness 2.32 (1.37–3.93)* 3.17 (1.69–5.95)* 2.18 (1.29–3.70)*
Indoor painting 1.42 (0.91–2.21) 1.23 (0.68–2.23) 1.11 (0.71–1.73)
Any wall-to-wall-carpet 0.64 (0.40–1.01) 0.72 (038–1.38) 0.79 (0.50–1.24)
a Subjects with onset of at least one symptom classified as general.
b Relative risk (RR) and 95% confidence interval.
c Subjects with onset of at
least one symptom classified as skin. d Subjects with onset of at least one symptom classified as mucosal. *p < 0.05
Table II. The prevalence of environmental factors in the current
dwelling of subjects who participated both in the initial study 1991
and in the follow up in 2001.
1991 2001 p-value a
Any type of pet at home 40 36 0.09
Indoor painting in the last
30 25 0.10
General mechanical ventilation
(in bedroom or living room)
20 22 0.32
Other type of odour
(mouldy odour excluded)
7.9 1.8 0.0001
Water leakage last 12 months 11 7.3 0.10
Signs of floor dampness
last 12 months
5.8 3.3 0.08
Visible moulds last 12 months 5.3 1.5 0.002
Mouldy odour last 12 months 2.8 0.5 0.008
Any type of building dampness b
18 24 0.02
a Differences tested by McNemar statistical test.
b Subjects report-
ing at least one factor regarded as dampness.
Sick building syndrome and domestic exposure: cohort study in Sweden 235
Furthermore, those with hay fever had a higher
incidence for skin symptoms and mucosal symptoms,
and a lower remission for skin symptoms. In addition
subjects living in damp dwellings had a lower remis-
sion of general symptoms and skin symptoms, and
those in dwellings that had been painted indoors had
a lower remission of general symptoms. In our study
the incidence of asthma had numerically increased
and the prevalence of hay fever had increased. This is
in accordance with other studies on asthma in the
Some methodological issues in this study need to
be addressed. The study is solely based on self-
reported data with no objective measurement, and
the information on building dampness in the longi-
tudinal analysis was collected retrospectively.
Moreover, good reproducibility of self-administered
questions on building humidity, visible moulds, and
flooding has been reported [23,24]. The questions
used in this study have been validated in earlier
studies by Norbäck et al. (1999) with regard to the
relationship between observed and self-reported
dampness. The sensitivity and specificity for the
presence of at least one sign of building dampness
were 74% and 71% respectively.
Recall bias can be a potential problem, as is the
possibility that the subjects overestimate or underes-
timate their personal symptoms and/or signs of
indoor dampness. Moreover, studies have established
that there was no difference in the reporting rate of
indoor dampness between symptomatic and asymp-
tomatic subjects  and that both groups tended to
underestimate the true observed indoor dampness
. Selection bias can occur, both because of an
incorrect study design and as a result of a low
response rate. The response rate in the initial study
was 70%, and of these 61% participated in the
follow-up study. Furthermore, the participants who
were lost during follow up did not differ from the
participants in baseline characteristics on age,
gender, hay fever, doctor’s diagnosed asthma, or
smoking habits. Thus, we would not expect any
major bias due to drop outs. One limitation however
is that the long follow-up period may lead to transient
symptoms related to exposure being missed, and only
permanent symptoms remaining after exposure being
Visible indoor moulds, mouldy odour, other type
of odour and any type of building dampness had
decreased significantly, possibly due to better main-
tenance and other improvements, suggesting less risk
for impaired health. Moreover, the number of dwell-
ings with mechanical ventilation had slightly
increased. The prevalence of any building dampness,
water leakage, sign of floor dampness and visible
moulds had decreased during the study period. This
illustrates that the increased focus on damp buildings
in Swedish dwellings have resulted in indoor envi-
ronmental improvements. A large amount of subjects
had painted indoors during the follow-up period. We
found that solvent-based paints were more com-
monly used by subjects renovating their dwelling
compared with those who used professional painters.
Studies on indoor painting show that professional
painters in Sweden almost exclusively use water-
based paints . Although subjects renovating their
dwelling were using solvent-based paints to a larger
extent, we did not find any relation between onset of
any symptoms and use of solvent-based paints.
However, the remission from general symptoms was
less likely in subjects who had their home painted
indoors with any type of paint.
A higher onset of general, skin and mucosal
symptoms was observed for all subjects with any
type of dampness in the dwelling. Analyses for
specific symptoms showed that subjects with any
type of dampness in the dwelling also had a
significantly higher onset for throat symptoms and
eye symptoms. Two review articles by Bornehag et al.
(2001, 2004) have concluded that building dampness
Table IV. Relationship between remission of weekly symptoms, building factors and personal factors.
Type of symptoms
(RR 95% CI) b
(RR 95% CI) b
(RR 95% CI) b
Female gender 0.79 (0.43–1.47) 0.62 (0.18–2.05) 0.80 (0.41–1.55)
Age (10y) 1.11 (0.82–1.48) 1.00 (0.43–1.22) 0.90 (1.00–18.66)
Hay fever 2.18 (0.99–4.19) 0.18 (0.05–0.70)* 0.47 (0.19–1.14)
Current tobacco smoker 1.28 (0.59–2.79) 0.74 (0.20–2.74) 0.92 (0.39–2.16)
Any type of building dampness 0.48 (0.23–0.99)* 0.24 (0.07–0.83)* 0.46 (0.21–1.02)
Indoor painting 0.43 (0.21–0.86)* 0.51 (0.15–1.69) 1.13 (0.56–2.27)
Any wall to wall carpet 1.57 (0.80–3.10) 1.42 (0.41–4.97) 1.21 (0.58–2.53)
a Subjects with remission of all symptoms classified as general.
b Relative risk (RR) and 95% confidence interval.
c Subjects with remission of
all symptoms classified as skin. d Subjects with remission of all symptoms classified as mucosal. *p < 0.05
236 B. Sahlberg et al.
is a risk factor for airway symptoms and also other
symptoms such as tiredness and headache, but these
conclusions are mainly based on cross-sectional data.
In addition, our results show that remission from
general symptoms or skin symptoms was less likely in
subjects with any type of dampness in the dwelling.
Similar results have been presented for respiratory
symptoms and building dampness .
No major sex, regional and seasonal difference was
observed for the association between dampness in the
dwelling and onset of symptoms. To our knowledge,
studies on seasonal or regional differences on asso-
ciations are rare. Our data indicate that tobacco
smoking might enhance the effect of building damp-
ness on incidence of SBS, but this finding needs to be
confirmed in larger studies.
In cross-sectional data female sex has been shown
to be an important risk factor for SBS symptoms
[3–6]. but our incidence data imply that there is no
difference in onset of SBS between females and
males. One cause of this discrepancy could be that
most other studies on SBS are cross-sectional and
present prevalence for SBS symptoms.
In conclusion, dampness and moulds in the dwell-
ing are a risk factor for onset of new SBS symptoms.
In addition, subjects living in damp dwellings have a
lower remission of general and skin symptoms.
Moreover, hay fever may increase the onset and
decrease the remission from SBS. Smoking may
enhance the association between dampness and
onset of SBS symptoms. The substantial reduction
of tobacco smoking in Sweden is expected to have a
beneficial impact on public health, with less exposure
to environmental tobacco smoke and less smoke-
related diseases in the future.
This study was supported by Uppsala University
hospital in Uppsala Sweden.
 Norback D, Edling C. Environmental, occupational, and
personal factors related to the prevalence of sick building
syndrome in the general population. Brit J Ind Med
 World Health Organization. Indoor air pollutants: exposure
and health effects. Report on WHO meeting. WHO
Regional Office for Europe: EURO Reports and Studies
 Apter A, Bracker A, Hodgson M, Sidman J, Leung WY.
Epidemiology of the sick building syndrome. J Allergy Clin
Immunol 1994;94(2 Pt 2):277–88.
 Mendell MJ. Non-specific symptoms in office workers: a
review and summary of the epidemiological literature.
Indoor Air 1993;3(4):227–36.
 Hodgson M. The sick-building syndrome. Occup Med
 Bjornsson E, Janson C, Norback D, Boman G.
Symptoms related to the sick building syndrome in a general
population sample: associations with atopy, bronchial hyper-
responsiveness and anxiety. Int J Tuberc Lung Dis
 Seppanen OA, Fisk WJ, Mendell MJ. Association of venti-
lation rates and CO2 concentrations with health and other
responses in commercial and institutional buildings. Indoor
 Wargocki P, Wyon DP, Sundell J, Clausen G, Fanger PO.
The effects of outdoor air supply rate in an office
on perceived air quality, sick building syndrome
(SBS) symptoms and productivity. Indoor Air 2000;10(4):
 Bornehag CG, Blomquist G, Gyntelberg F, Jarvholm B,
Malmberg P, Nordvall L, Nielsen A, Pershagen G,
Sundell J. Dampness in buildings and health. Nordic
interdisciplinary review of the scientific evidence on
associations between exposure to ‘‘dampness’’ in buildings
and health effects (NORDDAMP) [See comment]. Indoor
 Peat JK, Dickerson J, Li J. Effects of damp and mould in the
home on respiratory health: a review of the literature. Allergy
 Husman T. Health effects of indoor-air microorganisms [See
comment]. Scand J Work, Environ Health 1996;22(1):5–13.
 Engvall K, Norrby C, Norback D. Sick building syndrome in
relation to building dampness in multi-family residential
buildings in Stockholm. Int Arch Occup Environ Health
 Wieslander G, Norback D, Bjornsson E, Janson C,
Boman G. Asthma and the indoor environment: the signif-
icance of emission of formaldehyde and volatile organic
compounds from newly painted indoor surfaces. Int Arch
Occup Environ Health 1997;69(2):115–24.
 Norback D, Bjornsson E, Janson C, Widstrom J, Boman G.
Asthmatic symptoms and volatile organic compounds,
formaldehyde, and carbon dioxide in dwellings. Occup
Environ Med 1995;52(6):388–95.
 Andreas S, Herth FJ, Rittmeyer A, Kyriss T, Raupach T.
Smoking, chronic obstructive pulmonary disease and lung <
We are a professional custom writing website. If you have searched a question and bumped into our website just know you are in the right place to get help in your coursework.
Yes. We have posted over our previous orders to display our experience. Since we have done this question before, we can also do it for you. To make sure we do it perfectly, please fill our Order Form. Filling the order form correctly will assist our team in referencing, specifications and future communication.
2. Fill in your paper’s requirements in the "PAPER INFORMATION" section and click “PRICE CALCULATION” at the bottom to calculate your order price.
3. Fill in your paper’s academic level, deadline and the required number of pages from the drop-down menus.
4. Click “FINAL STEP” to enter your registration details and get an account with us for record keeping and then, click on “PROCEED TO CHECKOUT” at the bottom of the page.
5. From there, the payment sections will show, follow the guided payment process and your order will be available for our writing team to work on it.
Need this assignment or any other paper?
Click here and claim 25% off
Discount code SAVE25