Content uploaded by Tamara Gelderman
All content in this area was uploaded by Tamara Gelderman on May 01, 2020
Content may be subject to copyright.
Forensic Science, Medicine and
Forensic Sci Med Pathol
The correlation between the Aquatic
Decomposition Score (ADS) and the post-
mortem submersion interval measured in
Accumulated Degree Days (ADD) in bodies
recovered from fresh water
Guido Reijnen, H.Tamara Gelderman,
Bernice F.L.Oude Grotebevelsborg, Udo
J.L.Reijnders & Wilma L.J.M.Duijst
Your article is protected by copyright and
all rights are held exclusively by Springer
Science+Business Media, LLC, part of
Springer Nature. This e-offprint is for personal
use only and shall not be self-archived in
electronic repositories. If you wish to self-
archive your article, please use the accepted
manuscript version for posting on your own
website. You may further deposit the accepted
manuscript version in any repository,
provided it is only made publicly available 12
months after official publication or later and
provided acknowledgement is given to the
original source of publication and a link is
inserted to the published article on Springer's
website. The link must be accompanied by
the following text: "The final publication is
available at link.springer.com”.
The correlation between the Aquatic Decomposition Score (ADS)
and the post-mortem submersion interval measured in Accumulated
Degree Days (ADD) in bodies recovered from fresh water
&H. Tamara Gelderman
&Bernice F. L. Oude Grotebevelsborg
&Udo J. L. Reijnders
Wilma L. J. M. Duijst
Accepted: 18 April 2018
#Springer Science+Business Media, LLC, part of Springer Nature 2018
The Aquatic Decomposition Score (ADS) made by van Daalen et al., was developed to approximate the Post-Mortem
Submersion Interval (PMSI) in bodies recovered in salt water. Since the decomposition process in salt water differs from the
process in fresh water due to salinity, the temperature, and the depth of the water, we wanted to investigate whether there is a
correlation between the ADS and the PMSI and if the ADS can be used to make an estimation of the PMSI in bodies recovered
from fresh water. For the latter, the PMSI was measured using Accumulated Degree Days (ADD). In our study we included
seventy-six human remains found outdoors in fresh water. Their decomposition was measured using the ADS. A strong corre-
lation was found between the ADS and the PMSI. Also, it was found that the ADS can significantly estimate the ADD. Despite
the more varied circumstances under which bodies in fresh water are found when compared to those found in salt water, the ADS
can be used to measure the decomposition and accurately estimate the ADD, and thus the PMSI. More research is needed to
validate our method and make a prediction model with smaller confidence intervals.
Keywords Post-mortem submersion interval .Decomposition .Aquatic Decomposition Score .Accumulated Degree Days .
Drowning .Fresh water
Drowning is a manner of death which occurs frequently all
over the world. According to the World Health Organization,
every year 360,000 people drown . The circumstances un-
der which people drown can be accidental, suicidal, or even
homicidal. The post-mortem submersion interval (PMSI), the
time between death and the recovery of human remains from
the water, is of great importance in the reconstruction of the
events that led to death.
Multiple methods have been developed to estimate the
PMSI. Methods involving the natural growth of biofilms con-
taining algal, bacterial, fungal and protozoan species have
been investigated and are promising [2–4]. Unfortunately,
most of these methods require intensive laboratory analysis
and thus they are not able to estimate the PMSI at the scene
of the recovery. Another method used to estimate the PMSI
involves measuring the degree of decomposition of the recov-
ered human remains. For example, the Total Decomposition
Score (TDS) method was developed for human remains found
H. Tamara Gelderman
Bernice F. L. Oude Grotebevelsborg
Udo J. L. Reijnders
Wilma L. J. M. Duijst
Amsterdam Public Health Service, Amsterdam, The Netherlands
Rijnstate Hospital Arnhem, Arnhem, The Netherlands
IJsselland Public Health Service, Zwolle, The Netherlands
Netherlands Forensic Institute (NFI), The Hague, The Netherlands
Faculty of Law and Criminology, Maastricht University,
Maastricht, The Netherlands
Forensic Science, Medicine and Pathology
Author's personal copy
on land . This method used for bodies found on land was
adjusted for bodies found in water by Heaton et al. . The
Aquatic Decomposition Scoring (ADS) method of Heaton et
al. has been the subject of much research . Humphreys et al.
compared Heaton’s ADS method with the mass analysis
method and found the former was the more accurate and the
less compromising method for determining and evaluating the
level of decomposition for human remains found in fresh wa-
ter . De Donno et al. also studied Heaton’s ADS method
and found it promising, but concluded that determining the
PMSI is still extremely difficult due to wide biological vari-
However, the adjusted scoring method for bodies found in
water has not been validated. Recently, van Daalen et al. de-
veloped the Aquatic Decomposition Scoring (ADS) method
to estimate the PMSI of bodies recovered from salt water .
This method was derived from Megyesi et al. , who quan-
tified the stage of decomposition of bodies recovered from
open air in a total decomposition score. This score is based
on the decomposition stages of three different areas of the
body: the face and neck; the body; and the limbs. The van
Daalen et al.  ADS divides the body in the same manner.
The Total Aquatic Decomposition Score (TADS) is the com-
bined scores for these three areas. The ADS describes specific
aquatic decomposition phenomena divided into six stages. A
validation test was carried out with high outcomes. The ADS
method developed by van Daalen et al.  differs from the one
developed by Heaton et al. . Instead of a maximum TADS
of 25, van Daalen’s ADS has a maximum TADS of 18. In the
ADS method of van Daalen et al., phenomena are added to-
gether in one stadium, while in Heaton et al.’s they are given
their own score [6,9].
The literature shows that the salinity of water greatly influ-
ences the decomposition process. For example, a high saline
concentration in water reduces the bacterial activity [8,10,11].
Temperature also influences the decomposition process, as the
process is accelerated in warmer waters . The temperature
of the water is influenced by depth, since sunlight rarely pen-
etrates deeper than two meters . Depth also influences de-
composition itself. When a body isbelow a certain water depth
(approximately 61 m), bloating does not occur (due to high
pressure) and thus the body will not float or wash ashore
[12–14]. The more varied levels of decomposition of human
bodies recovered from fresh water may adversely affect the
accuracy of the decomposition score.
In recent years, multiple studies have investigated the use of
ADD and TADS to calculate or estimate the PMSI [7,8]. The
ADD is the sum of the average daily ambient temperatures
between the date of death and the date of recovery. It represents
the heat energy units needed for the biological and chemical
reactions to decompose a body . The ADD has not (yet)
been used to estimate the PMSI with the ADS developed by
vanDaalenetal. for bodies recovered in fresh water.
This study describes the correlation between the ADS de-
veloped by van Daalen et al. and the PMSI and between
the TADS and the ADD (and thus the PMSI) in bodies recov-
ered from fresh water.
In this retrospective study, bodies recovered from outdoor
fresh water in Amsterdam, the Amsterdam region, and the
IJsselland region, all located in the Netherlands, between
March 2008 and July 2017 were included. Fresh water was
defined as water having a sodium chloride content of less than
nine grams per liter.
All included cases of bodies recovered from water were
‘closed’, which means there was no ongoing (criminal) inves-
tigation at the time of data analysis. For the body to be includ-
ed, the personal data of the deceased person had to be known
and a post-mortem report had to be available. This included a
known PMSI and full color photographs of the face, limbs and
the body. Children under the age of 18 years were excluded
because their body surface area –body content ratio is higher
compared to that of adults . Moreover, children have a
different distribution of body surface area due to their propor-
tionally larger heads and smaller lower extremities .
Bodies recovered from indoor fresh water were also excluded.
Seventy-six cases were included, of which there were 61
males (80.3%) and 15 females (19.7%). The mean age was
52 years with a minimum of 18 and a maximum of 83. The
types of water in which the human remains were found in-
cluded ditches (n=13),canals(n= 14), channels (n= 9), riv-
ers (n= 19), ponds (n= 6), puddles (n= 4), lakes (n= 5), other
(n= 1) and unknown (n= 5). Thirty-five individuals passed
away after an accident and 26 after committing suicide. In
15 cases, the manner of death was unknown.
The decomposition scoring method of van Daalen et al. 
was used to measure the level of decomposition. This decom-
position scoring method divides the sequential pattern of the
decomposition process into six stages, each containing specif-
ic phenomena. The human body is divided into three anatom-
ical regions (face and neck, body, and limbs). Each region can
be appointed a value from 1 to 6. The TADS is equal to the
sum of these three values. A score of 3 means no visible
changes and a score of 18 means complete skeletonization.
To guide the users of the decomposition scoring method, an
explanation of the decomposition stages and phenomena has
been developed, as well as a pictorial reference atlas. The
reference atlas contains photographic examples of all the phe-
nomena occurring in the decomposition process.
Forensic Sci Med Pathol
Author's personal copy
A senior forensic physician, with no experience with this
method outside the received verbal instructions described be-
low, scored all 76 included cases. This forensic physician had
no knowledge of the cases, so the scoring was blinded to
prevent bias. Previous research has shown that the ADS has
a strong agreement between scorers (who ranged from medi-
cal doctors to police officers). The Krippendorff’s alpha scores
were between 0.93 and 0.96, where scores over 0.80 are con-
sidered to be high [9,18]. Because of this strong agreement,
scoring in this study could be done by one forensic physician.
Before scoring any of the 76 cases, the forensic physician
received verbal instructions regarding the decomposition scor-
ing method and how to use the pictorial reference atlas. The
forensic physician was instructed to start with the highest
stage and work his way down, until the decomposition stage
containing the visible phenomena was reached. When multi-
ple phenomena were present, the highest score was to be re-
corded. After the three anatomical regions were scored by the
forensic physician, the TADS was calculated by the
The ADD is the sum of the mean daily water temperatures
between the time of death and the recovery date. The water
temperature data was provided by the executive agency of the
Ministry of Infrastructure and Water Management
(Rijkswaterstaat) . Because we had to deal with different
water types and many different locations, we chose to use the
water temperature from two points in the Amsterdam region.
For the bodies found between 2008 and 2013, we used record-
ings near the Amsterdam IJtunnel. These recordings were
made approximately 1 to 3 times per month. From the years
2013 up to and including 2017, there were daily recordings of
the water temperature at the former NDSM shipyard (approx-
imately 2.5 km north-west of the IJtunnel recordings).
The ADD was calculated by adding up the average daily
water temperatures from the date the body was found back to
the date of death.
The statistical analysis was conducted using SPSS, version
24.0 (SPSS Inc.) and Software R and R studio. The
Spearman correlation coefficient was used to test the correla-
tion between the aquatic decomposition score and the PMSI.
The ADD and TADS were used to produce a linear regression
model with the ADD as the independent variable. We trans-
formed the ADD with the logarithm (log 10). The TADS was
rescaled from 3 to 18 to 0–15 by subtracting 3. Software R and
R studio was used to make estimates of the ADD with
prediction intervals for every TADS score using inverse pre-
diction. The statistical method is based on Moffat et al. .
This study was approved by the Public Health Service
Amsterdam and the Public Health Service IJsselland and per-
formed according to the ethical and legal standards in the
Netherlands. All data were processed anonymously.
In the research population, the TADS rescaled ranged
from 0 (no visible changes) to 10 (extensive decomposi-
tion). In 42 cases there were no visible changes, in 9 cases
there was one decomposition phenomenon visible, and in
25 cases there were two or more decomposition phenom-
The ADD ranged from 3.7 to 6245.8. Twenty cases had an
ADD below 10. Forty-four cases had an ADD between 10 and
100, nine between 101 and 1000 and three cases had an ADD
higher than 1001. The last three cases, with an ADD of
1259.0, 1398.7 and 6245.8 respectively are considered to be
outliers, but were not removed from the analysis because they
are part of daily practice. The fourth highest ADD is 611.6.
TADS versus PMSI
The correlation between the decomposition and PMSI was
measured for the three body regions separately and for the
combination of these (TADS). The highest correlation was
found between LADS and the PMSI, followed by the corre-
lation between TADS and PMSI (Table 1). The correlation
between FADS and PMSI was very close to the correlation
Table 1 ADS versus PMSI
Spearman’s rho FADS 0.754 <0.001
BADS 0.754 <0.001
LADS 0.846 <0.001
TADS 0.818 <0.001
ADS as made by van Daalen et al.
PMSI Post-Mortem Submersion Interval, FA D S Facial Aquatic
Decomposition Score, BADS Body Aquatic Decomposition Score,
LADS Limbs Aquatic Decomposition Score, TADS Total Aquatic
Decomposition Score, p = p-value
Forensic Sci Med Pathol
Author's personal copy
between BADS and PMSI. Although the lowest correlation is
0.754, this is still considered a strong correlation .
Correlation between TADS and ADD
The correlation between decomposition (TADS) and ADD
was measured and was strong (N= 76, Spearman’sρ=
0.707, p<0.001). The TADS can be used to predict the
ADD using the following formula:
TADS rescaled ¼4:055 x Log ADDðÞ−3:836:
This model fits the data well (R
= 0.782); the regression
line is shown in Fig. 1.
We have developed a prediction model with an estimated
ADD with a confidence interval for every TADS. Table 2
shows the values of the confidence interval. These values
were log transformed to make Fig. 2.
As previously mentioned, bodies recovered from fresh wa-
ter are exposed to different variables compared to bodies
recovered from salt water . The aim of this study was to
investigate whether the recently published ADS developed
by van Daalen et al.  can also be used to measure de-
composition for bodies recovered from different types of
fresh water and to make a correlation with the PMSI. We
decided not to exclude the outliers because they are part of
daily practice. We realize that this makes our outcomes
potentially less favorable than they would be if the outliers
Our results showed a strong correlation between the FADS
and BADS with the PMSI and a very strong correlation
between the LADS and TADS with the PMSI. We conclude
that the ADS can be used for measuring the degree of decom-
position in bodies recovered from fresh water.
The TADS is strongly correlated with the ADD, despite our
heterogeneous population with outliers. An advantage of the
ADS compared with other decomposition scores is that the
decomposition can be scored at the scene of the recovery
and no autopsy is required. Another advantage of this method
is that it is less time consuming than other methods, such as
Fig. 2 Log confidence interval lines per TADS. TADS Total Aquatic
Decomposition Score, ADD Accumulated Degree Days, CI
Table 2 TADS and predicted ADD using inverse prediction
TADS rescaled Predicted ADD Lower 95% CI Upper 95% CI
0 8.8 2.1 37
2 27.5 6.6 114.6
4 85.6 20.4 359.8
5 151 35.6 640.8
6 266.4 62 1145
7 470.1 107.6 2053
8 829.5 186.3 3692
9 1464 321.6 6660
10 2582 553.4 12,048
11 4556 949.9 21,855
12 8039 1626 39,745
13 14,185 2777 72,458
14 25,028 4731 132,399
15 44,161 8044 242,449
TAD S Total Aquatic Decomposition Score, ADD Accumulated Degree
Days, CI Confidence Interval
Fig. 1 Plot of Total Aquatic Decomposition Score vs. Log transformed
Accumulated Degree Days. R
Forensic Sci Med Pathol
Author's personal copy
those involving the natural growth of biofilms, and no specific
expertise is needed [2,3,22].
We conclude that for bodies recovered from fresh water,
there is a correlation between the TADS and the ADD. The
strength of this study is that cases from different types of water
were included and these cases are from a general forensic
practice. What makes this model especially useful in practice
is that the water temperature of a general measuring point can
be used. Thus the model can be used even if the temperature of
the water in which a deceased person is found is unknown.
Future research could compare van Daalen’s ADS method
to other methods to investigate the accuracy of both methods.
Validating other methods by using this method is discouraged,
however, since there are limitations of this study which need
to be addressed first.
This research has certain limitations. It is a retrospective
study and the scoring is based on photographs. Some cases
lacked sufficient photographs of certain body parts. In some
cases, only pictures of the divergences were made, while the
other parts of the body were not recorded in detail. The ab-
sence of pictures from these parts can potentially lead to an
underestimation of the TADS. In a prospective study, when
scoring is performed on site, this limitation can be avoided.
Bodies with no visible decomposition are relatively over-
represented in our general practice (N=42(55.3%),TADS=
3). Most of these individuals were reported missing and found
soon after a search was started. In other cases, bystanders saw
individuals going for a swim, for example, but they never
returned or a body was seen floating in the water. In these
cases, emergency aid was started quickly and the remains
were not in the water long enough for decomposition phenom-
ena to become visible.
Unfortunately, there were 58 cases (76.3%) with an ADD
between 0 and 50. Future prospective studies would benefit
from more cases with a higher ADD and advanced decompo-
sition and also to validate the results found in this research.
The exclusion of outliers should be avoided because they are
present in the daily practice.
In this study there was no differentiation made between
complete submersion and partial submersion. In some cases,
the body was partially exposed to air, either because the water
was shallow or the body was already floating as a result of
ongoing decomposition. As decomposition on land differs
from decomposition in water , the exposure to air could
have an influence on the TADS in our study.
Humphreys et al.  tested the TADS method developed
by Heaton et al.  and found a different logarithmic re-
gression line compared to the one found by Heaton et al.
The authors mention that this was expected because the
methods in the two studies differed from each other (human
remains vs. perinatal piglets and U.K. waterways vs. agri-
cultural reservoir); however, it should be stated that their
regression line is based on a natural logarithm (with a base
of 2.7) instead of the base 10 logarithm used by Heaton et
al. . The authors also described the need to determine the
appropriate ADD and TADS equation for every location in
which human remains are found. In our study we have de-
veloped one model that fits for multiple locations and types
of water in the Netherlands using a general water tempera-
ture measurement point.
In addition to the correlation previously found between van
Daalen’s ADS and the PMSI in bodies recovered from salt
water, there is a strong correlation between van Daalen’s
ADS and bodies recovered from fresh water. Thereby, there
is also a strong correlation between the ADS and the ADD of
bodies recovered from fresh water. These correlations were
found despite the various circumstances under which bodies
were found in fresh water compared to those found in salt
water. We conclude that the ADS is usable in measuring the
decomposition and in a prediction model to accurately predict
the ADD for bodies recovered from fresh water. More re-
search is needed to validate this model with use of future cases
and to make a prediction model with smaller confidence
1. There is a strong correlation between the Aquatic
Decomposition Score and the Accumulated Degree Days.
2. The Aquatic Decomposition Score can be used to predict
the time of death in bodies recovered from fresh water.
3. The Aquatic Decomposition Score is applicable under
4. More research is needed to make a more accurately pre-
diction model using the Accumulated Degree Days.
Acknowledgments The authors would like to thank Mr. W Heutz (inde-
pendent forensic physician) for scoring the 76 cases.
Funding This research did not receive any specific grant from funding
Compliance with ethical standards
Conflict of interest The authors declare that they have no conflict of
1. World Health Organization. Violence and injury prevention and
disability. 2004. http://www.who.int/mediacentre/factsheets/fs347/
en/. Accessed 17 Aug 2017.
Forensic Sci Med Pathol
Author's personal copy
2. Benbow ME, Pechal JL, Lang JM, Erb R,Wallace JR. The potential
of high-throughput metagenomic sequencing of aquatic bacterial
communities to estimate the postmortem submersion interval. J
Forensic Sci. 2015;60:L1500–10.
3. Zimmerman KA, Wallace JR. The potential to determine a post-
mortem submersion interval based on algal/diatom diversity on
decomposing mammalian carcasses in brackish ponds in
Delaware. Forensic Sci. 2008;53:935–41.
4. Lang J, Erb R, Pechal J, Wallace J, McEwan R, Benbow M.
Microbial biofilm community variation in flowing habitats: poten-
tial utility as bioindicators of postmortem submersion intervals.
5. Megyesi MS, Nawrocki SP, Haskell NH. Using accumulated
degree-days to estimate the post mortem interval from decomposed
human remains. J Forensic Sci. 2005;50:618–26.
6. Heaton V, Lagden A, Moffat C, Simmons T. Predicting the post-
mortem submersion interval for human remains recovered from
U.K. waterways. J Forensic Sci. 2010;55:302–7.
7. Humphreys MK, Panacek E, Green W, Albers E. Comparison of
protocols for measuring and calculating postmortem submersion
intervals for human analogs in fresh water. J Forensic Sci.
8. De Donno A, Campobasso CP, Santoro V, Leonardi S, Tafuri S,
Introna F. Bodies in sequestered and non-sequestered aquatic envi-
ronments: a comparative taphonomic study using decompositional
scoring system. Sci Justice. 2014;54:439–46.
9. van Daalen MA, de Kat DS, Oude Grotebevelsborg BFL, Warnaar
J, Oostra RJ, Duijst-Heesters WLJM. An aquatic decomposition
scoring method to potentially predict the postmortem submersion
interval of bodies recovered from the North Sea. J Forensic Sci.
10. Boyle S, Galloway A, Mason RT. Human aquatic taphonomy in the
Monterey Bay area. In: Haglund WD, Sorg MH, editors. Forensic
taphonomy. The postmortem fate of human remains. Boca Raton:
CRC Press; 1997. p. 605–13.
11. Byard RW. Putrefaction - an additional complicating factor in the
assessment of freshwater drownings in rivers. J Forensic Sci. 2017.
12. Anderson GS, Bell LS. Deep coastal marine taphonomy: investiga-
tion into carcass decomposition in the Saanich Inlet, British
Columbia using a baited camera. PLoS One. 2014;9:e110710.
13. Anderson GS, Bell LS. Comparison of faunal scavenging of sub-
merged carrion in two seasons at a depth of 170m, in the strait of
Georgia, British Columbia. Insects. 2017;8:e33.
14. Anderson GS. Decomposition and invertebrate colonization of ca-
davers in coastal marine environments. In: Amendt J, Goff ML,
Campobasso CP, Grassberger M, editors. Current concepts in fo-
rensic entomology. New York: Springer; 2010. p. 223–72.
15. Simmons T, Adlam RE, Moffatt C. Debugging decomposition da-
ta—comparative taphonomic studies and the influence of insects
and carcass size on decomposition rate. J Forensic Sci. 2010;55:
16. Bijl D, Semmekrot B, van Loenen A. Farmacotherapie. In: Bindels
PJE, Kneepkens CMF, editors. Kindergeneeskunde. Houten, NL:
Bohn Stafleu van Loghum; 2013. p. 85–6.
17. Rice PL, Orgill DP. Classification of burns. http://www.uptodate.
Accessed 17 Aug 2017.
18. Krippendorff K. Content analysis: an introduction to its methodol-
ogy. 3rd ed. Thousand Oaks: Sage; 2013.
19. Rijkswaterstaat. http://waterinfo.rws.nl/#!/nav/index/. Accessed 18
20. Moffatt C, Simmons T, Lynch-Aird J. An improved equation for
TBS and ADD: establishing a reliable postmortem interval frame-
work for casework and experimental studies. J Forensic Sci.
21. Statstutor. Spearman’s correlation. https://www.statstutor.ac.uk/
resources/uploaded/spearmans.pdf. Accessed 31 Dec 2017.
22. Haefner JN, Wallace JR, Merritt RW. Pig decomposition in lotic
aquatics: the potential use of algal growth in establishing a post-
mortem submersion interval (PMSI). J Forensic Sci. 2004;49:330–
23. Lunetta P. Drowning. In: Madea B, editor. Handbook of forensic
medicine. Hoboken: Wiley Blackwell; 2014. p. 411–27.
Forensic Sci Med Pathol
Author's personal copy
Preview content only
Content available from Forensic Science Medicine and Pathology
This content is subject to copyright. Terms and conditions apply.