A 2021 systematic review of research into child neglect and child abuse has shown little direct evidence for three factors – substance misuse, parental mental illness and domestic violence – in child abuse.
It therefore calls for children’s social services and policymakers to not put such weight that the so-called ‘toxic trio’ is in itself that evidence that a child may come to harm if these factors are present in their parents.
In this article we will summarise the research, discussing what it found and what needs to be done to harden any evidence base that has been missed to date.
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Over the years, the idea that behaviours or circumstantial factors in a child’s parents have come to be accepted as future risk factors for their children.
Though it is inarguable that factors associated with poverty can underly poor childhood outcomes, these are large in number.
Poor housing can lead to poor health and poor mental health, for example.
Unstable employment on the part of the parents can lead to the same.
Among as many as 40 other factors, only 5 have been highlighted as the greatest risk factors:
When substance misuse and/or alcohol misuse are combined alongside mental health issues and learning disabilities, this has become conflated into a ‘toxic trio’.
According to this systematic review, one of the first papers to coin the term ‘toxic trio’ was a review of Serious Case Reviews in 2010.
Around 100 Serious Case Reviews (SCRs) are done annually and are government-led inquiries into the serious harm or death of a specific child.
These reviews of SCRs would therefore highlight findings in the worst cases of child abuse in England at the time.
The term gained currency in social work after the Association of Directors of Children’s Services (ADCS) picked up on it and, come 2013 the idea had filtered through CAFCASS and the family court system.
In 2018 researchers discovered the use of the term by duty and assessment social workers at 14 sites across 6 local authorities, leading the researchers to state that it had firmly entered the lexicon of children’s social work.
The ADCS later said that the toxic trio concept was largely behind a surge in child protection cases among children’s social services in England.
In short, a fad concept had taken hold among social workers, which in turn led to many families undergoing court battles and investigations that may well have led many of those families to be split up.
So, is there any evidence behind the concept?
This systematic review looked at the evidence to see if there were links between the ‘trio’ and if so, what processes there are that link them to poor childhood outcomes.
For example, is an alcoholic mother in high likelihood going to beat or neglect their child? Will someone with depression or anxiety do the same?
If they are depressed and use heroin is the likelihood increased, and is it further increased if there is domestic violence at home?
A systematic review looks at existing research and seeks to highlight trends from that research.
This differs from lower-level research that seeks to use primary evidence to assess a hypothesis.
This paper set qualification criteria for the research it assessed, specifying that they had to:
Papers were rejected if, amongst other factors
From this search, the authors only found 20 papers that qualified – 15 from the UK, 3 from the USA, and 1 each from Canada and Ukraine.
8 of the papers were reviews of SCRs, a majority of which were written by the same team of authors – the very authors who had coined the term ‘toxic trio’ in the 2010 paper.
As we will see, there may have been an inherent bias in the research as a result.
The authors of this systematic review highlighted five weaknesses of the reviews of SCRs and other research papers.
We summarise these below:
An SCR is only done in the most extreme cases of harm or neglect.
There are fewer than 100 done annually in England, representing 0.025% of the 400,000 child-in-need cases in the last 10 years.
The SCR also represents just 0.16% of cases of children starting a child protection plan between 2012 and 2019 on basis of ‘actual or potential serious harm to the child’.
SCRs included amongst other things:
21% of SCRs between 2007-09 and 16% between 2009-11 were harm or neglect by professionals and people other than parents or guardians
The systematic review highlighted the fact that in the reviews in question:
When it came to substance misuse, this was vague across all research.
All papers displayed the following issues:
The extent of the mental illness or learning disability wasn’t highlighted.
A parent experiencing severe psychosis would be different to one medicated for depression, and many parents can look after their children even if they have schizophrenia.
The degree of domestic violence was also not explicitly stated.
The research did not include how the toxic trio factors were linked to the child abuse or neglect incident.
For example, these did not show that:
The lack of these specific links weakened the research.
Across all papers looked at in this systematic review, the only standardised measurements linking the toxic trio concept to poor child outcomes were percentages.
The percentages were of ‘X parents had [a factor] and this was in Y amount of cases of child abuse/neglect.’ This could only show that the cases happened but don not explain why.
Consequently, there was a difficulty in comparing the research as different scales were used each time.
There is a general understanding among scholars that a good piece of research should be repeatable and comparable to other research – since comparability is lacking, so all lacked any reliable credibility.
Where the ‘toxic trio’ concept was highlighted, many other factors were ignored in the conclusions in the SCRs.
These included:
With regard the other research, it ignored:
The systematic review highlighted poverty as an example behind many child abuse and neglect cases.
Relevant factors linked with poverty include:
All of these factors in any combination could form other ‘toxic trios’ that may be taken into common children’s social work lexicon, as opposed to the five in the current lexicon.
As we will see in the final section, a more nuanced understanding of a child’s welfare needs taking without using ‘fad terms’.
The authors of the systematic review concluded that the evidence is not of sufficient quality or depth to give any strength to the concept of the ‘toxic trio’.
If in future the five factors can with any great effect be considered as among the most dangerous factors for a child’s upbringing, then the authors stated that clear links need to be made between those and the outcomes.
As we have given in multiple examples above, this might be an intoxicated parent having a measurably higher chance of abusing or neglecting the child.
Fad terms also have the effect of stigmatising certain communities
Those with mental illness are automatically considered to have a ‘toxic behaviour’, as do those who have developed substance misuse disorders.
There is no good research that shows a person with a drug addiction is not capable of good enough parenting.
Until there is, science cannot back up these claims.
Boris is our editor-in-chief at Rehab 4 Addiction. Boris is an addiction expert with more than 20 years in the field. His expertise covers a broad of topics relating to addiction, rehab and recovery. Boris is an addiction therapist and assists in the alcohol detox and rehab process. Boris has been featured on a variety of websites, including the BBC, Verywell Mind and Healthline. You can connect with Boris online at LinkedIn or X.com.
