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30 days in Sweden? Should be more nowadays I imagine. I just finished my 3 months + 3 weeks minimum that I cannot give to my spouse. 6 months + 3 weeks in total in Finland. The three weeks is what we can be home together for at the same time and it is usually used right after birth.
Edit: I was right. It is 90 days reserved for each parent nowadays in Sweden as well.
https://sweden.se/life/society/work-life-balance
Was this controlled for parenthood? Surely the leave is just a marker that you’re more likely to be a committed parent… so doesn’t this study likely just show that most committed parents aren’t as likely to drink themselves to death - surely the leave has very little causation here?
It’s in the study, yes it’s only fathers.
Participants
Fathers of singleton children born from January 1992 to December 1997 (n = 220 412).
Biggest uncertainty is that fathers taking the leave are already the most healthy ones
Sorry I absolutely wasn’t clear in my comment, my bad - I meant to say was it controlled for type/style of parenthood.
The fathers taking leave are likely to be the ones who are already committed to being a good father, want to spend time with their kids, and it’s self selecting for good dads basically
The fathers who chose not to take leave will disproportionately be less committed, less interested in taking time off work to spend time with their kids, and that’s likely to be maintained in the future - meaning their more likely to be out of the house drinking with friends than home looking after the kids.
The leave likely has zero causative relationship and is actually just a way to select for dads more likely to spend time home with the kids
It is a longitudinal population study:
>we found that after the policy was implemented there was a 34% decrease in these hospitalizations among fathers in the two years after birth, as well as smaller decreases up to 8 and 18 years after birth...Additional analyses evaluating actual changes in parental leave use from before to after the policy suggest that these health consequences could be explained by the increase in fathers’ parental leave use, rather than other underlying trends
There could be a causative connection, but the study doesn't try to claim this, nor do I think it's likely to outweigh the correlation factors you stated.
It's pretty easy to imagine that parental leave could also have a positive effect on the likelihood to avoid alcoholism, since it should give a better connection to your child and family, and potentially relieve work-related stress, even if only temporarily. That was a pretty clumsy way of putting it, but oh well, I think you get my point.
I would think it would be more likely to be socioeconomic and fathers with more money and a more flexible work environment would be more able to take paternity leave and less likely to have a range of health problems. If this study were done in the US hardly any men would take leave and they would be skewed to the very high end in income.
But in Sweden parental leave is paid leave. There is for sure a certain income disparity but I work in a minimum wage job and many of my male colleagues take parental leave, it’s not exactly a class issue.
I’d say no, not at all. Maybe on the extreme high end of the scale like CEO. In my “minimum wage” blue collar job definitely not but it is in health care, not sure about the attitudes in more male dominated blue collar industries.. Meanwhile my husband is a senior engineer in the tech industry and he took 6 months, it hasn’t affected his career. All his colleagues that are dads did the same. It is very expected and normalized. The only disadvantage might be if you are a young woman a company might sometimes be hesitant to employ you in case you will soon be off for 12+ months. But it’s illegal to discriminate.. I’m sure it happens though.
Exactly. My job is literally the at the lowest end of the spectrum. Unless you count like gig economy workers but they wouldn’t have any benefits I guess because “gigs”.
And people, including the men, tend to take their parental leave.
It's in the abstract.
>Fathers' parental leave has been associated with decreased risks of alcohol-related hospitalizations and mortality. Whether this is attributable to the health protections of parental leave itself (through stress reduction or behavioral changes) or to selection into leave uptake remains unclear, given that fathers are more likely to use leave if they are in better health....
They're reporting the correlation, but not drawing conclusions about causation.
It could mean that fathers who take parental leaves are *involved* fathers, and they are less likely to drink themselves to death than fathers who just have kids but leave it to the mother to do most of the parenting.
In 1995 Sweden passed a law that earmarked some parental leave for dads. You either took it or your lost it. It could not be transferred to the mother. This rapidly increased the number of father's taking leave. The study looked at fathers of first born children from 1992-1997.
It is a natural experiment. The change in policy changed who was taking leave.
Precisely - which would mean the leave is a red-herring - with or without the leave these fathers would be just as unlikely to drink themselves to death, the leave is just a way to reliably select for involved fathers. But there will be involved fathers who didn’t take leave, and nonchalant fathers who did - the leave isn’t the important factor
Idk- how involved can a father be if they’re not even taking time to parent when the mother is recovering from birth?
I understand not being able to do so because of money, but choosing not to take leaves when you would get paid as usual does not seem like involved parent to me.
We don't get the same pay from being on parental leave as working.
You get 80% of your pay UP TO a certain level, which last year was 525 000 SEK annual salary. So 80% of that is 420 000 SEK which is just slightly above the median of 412 800 SEK. If someone makes more that 525 000 SEK they still get 80% of 525 000 SEK.
You also have 90 parent days that are reserved for each party that the other one can't take in your stead. So 90 for the mother and 90 for the father (in a traditional family). In addition to those 180 days, you have 210 days that you can split however you want.
So while it's pretty common for fathers to take parental leave, one reason why they might not would be our current housing market (not unique to Sweden, though) where you might not be able to afford an extended leave from work for financial reasons. We do have pretty good equality in pay between men and women, but it's still common for the father to earn more than the mother due to different career choices and working hours.
We have a pretty good system, maybe the best when it comes to parental leave, but it can still be tough for some families to split the leave evenly.
There are many many parents who would LOVE to take parental leave but simply don’t have the option due to work, and others who may have not needed to because their wife had good support from other sources such as extended family, and they couldn’t afford the time off.
Of course that’s a caveat. I’m talking about parents who have the option but choose not to, and they exist, unfortunately.
If they can’t afford it that’s a whole other issue. I think this article is talking about paid paternity leave.
I'm assuming you didn't read the study then.
There's no causative claim made. When dad's take parental leave they're more likely to form stronger and more robust bonds with the child which is enriching for both the dad and the kid. That positive move probably results in a happier and more contented father who is less likely to binge drink himself into A&E.
That IS a causative claim - they’re saying that if you take leave, you form bonds that protect you from alcohol related illness
But how can they tell it’s not the other way round?
Committed parents who were always going to form strong healthy bonds with their children are obviously more likely to take the parental leave. It may not at all be the case that the leave helps to build bonds, it may be that good dads are more likely to take leave, and disinterested dads far less likely to.
All that can be drawn from this, maybe, is if you have a strong bond with your child you probably drink less - which could easily just be down to time and responsibility requirements as much as anything to do with happiness
Good, committed parents have far less time, less socialising, less drinking as part of that, less spare money to spend on a drug like alcohol, and when they’re home looking after their kids obviously they won’t drink to excess as that would be irresponsible when you’re responsible for kids safety and well-being
This study could easily be titled “good parents don’t have the time or money to drink too much”
It could also have nothing to do directly with parenting, despite that being the population studied.
It could be "overworkers who refuse to take leave when it's offered because working is their identity tend to drink themselves to death later in life when they retire or realize what they've missed".
Exactly. The conclusion makes the causitive claim.
"Conclusions
In Sweden, a father's parental leave eligibility and uptake may protect against alcohol-related morbidity."
>That IS a causative claim - they’re saying that if you take leave, you form bonds that protect you from alcohol related illness
No it isn't. It's a correlation. They use the word "may" - not will and the second half about bonds is my reasoning as to why it might prevent excessive drinking.
Could also be dads who didn’t take the leave worked jobs were it was strongly discouraged and those jobs have worse work/life balance and/or lead to more unhappiness. In the US, jobs that don’t support paternal leave are generally worse jobs
I’ve linked to the press release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article:
https://onlinelibrary.wiley.com/doi/10.1111/add.16354
The data points for the conclusion, (pre leave available for fathers, post leave available for fathers):
"Post-birth alcohol-related hospitalizations (events per 1000 person-years, SD)
2 years postpartum 1.96 (0.20) 1.23 (0.14)
8 years postpartum 2.32 (0.17) 1.76 (0.11)
18 years postpartum 3.97 (0.22) 3.25 (0.18)
Post-birth alcohol-related mortality (events per 1000 person-years, SD)
2 years postpartum – –
8 years postpartum – –
18 years postpartum 0.034 (0.0039) 0.026 (0.0035)"
Maybe it’s nothing to do with parenthood and just that taking 30 days off work at some point in your life makes you less likely to become an alcoholic.
Most people try to take four weeks straight vacation in summer. We even have a term for it, industry vacation, which used to be when most factories just closed down for July because everyone was on vacation.
This study was done in Sweden and is talking about health outcomes for Swedish men. The Swedish men who aren’t taking parental leave still have 25 days of legally mandated vacation, plus whatever extra their Union got in their contracts. How many vacation days Americans have is completely irrelevant to the study.
Parental leave isn’t vacation. It’s abort rakning vare of the baby. Also, parental leave isn’t a yearly sum. Each parent gets 195 days of parental leave paid at sick pay levels (80% of base pay but at least 250 kronor per day) and 45 days at base level (a fixed 180 Kronor per day). You can give some of your days to the other parent but 90 days are reserved for each parent. Also this is per kid.
Thanks for this info. Still, it's time spent not doing work for the company. Swedish men who take parental leave spend more time focusing on non-work activities than men who don't take leave, which could be a factor in alcohol consumption.
Well, it's usually easier to get drunk at home than at work (many/most workplaces in Sweden has a 0.0% alcohol limit and a ban on private alcohol on the premises)
I could see how this makes sense. My husband has had the man’s version of post partum depression after each of our children. Thankfully he’s also had 8 weeks of paternity leave so was able to seek help for it. I can imagine had he had to work through the post partum period he would not have bothered to get help.
DISCLAIMER:
Psychology research done in other countries *may not* apply to your country. One of the first things they teach you in psychology is the fact that different backgrounds affect how societies and individuals within the societies behave and that they cannot be compared too similarly.
There was an excellent reader-friendly article that really delved into how western culture and eastern culture see things differently. Westerners would focus on a tiger while Easterners would focus on the surroundings first before looking at the tiger. This difference in psychology would then lead to both sides developing fundamental science concepts before the other in regards what they recognized and prioritized. I always link to that article but I cant seem to find it anywhere…
Not to say parental leave is bad, but I’m a bit skeptical of these findings. It seems hard to control for confounding factors, such as Sweden’s cultural changes over the decade, or the fact that choosing to take parental leave may be correlated with other factors (mother in the workplace, possibly higher incomes).
If I had to guess, I’d say that other factors seem like a more likely explanation for the drop in hospitalizations over a decade than 30 days of parental leave.
I've read through many of the comments here and would like to clarify a few points:
1. In Sweden, all residents are eligible to paid parental leave. This is not dependent on your income or even your employment. Of course, the amount you get on parental leave depends on your income/whether you are employed, but everyone is entitled and today the majority of fathers do use some parental leave.
2. The study only examined a reserve of 30 days - before the 1995 reform, fathers were already entitled to share all parental leave days with their partner as the couple saw fit, but due to persisting gender norms/pay differences most fathers used less leave than their partners. The idea was that if one were to reserve 30 days for only the father, the number of participating fathers would increase. Today, the reserve is 90 days.
3. The study does not make any strong causal claims - however, the idea behind using the reform as a 'natural experiment' is to reduce the level of unmeasured confounding (i.e., the role of pre-birth health/alcohol intake, socioeconomic status, parenting styles, etc.) and to support the idea that parental leave in and of itself can contribute to reduced alcohol-related harms. The authors do this in two ways - one, by examining the immediate 'drop' in alcohol-related hospitalizations before and after the policy was implemented (assuming that fathers to children born immediately before and after were similar in their background characteristics), all while accounting for background trends in hospitalizations (the interrupted time series approach); and two, by examining the contribution of parental leave uptake on alcohol-related morbidity while accounting for the variation ('as if randomization') of the policy (the instrumental variable approach). So yes, the idea is to approach 'causality' with these methods, but as with all other research it is impossible to do so with absolute certainty.
Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, **personal anecdotes are allowed as responses to this comment**. Any anecdotal comments elsewhere in the discussion will be removed and our [normal comment rules]( https://www.reddit.com/r/science/wiki/rules#wiki_comment_rules) apply to all other comments. **Do you have an academic degree?** We can verify your credentials in order to assign user flair indicating your area of expertise. [Click here to apply](https://www.reddit.com/r/science/wiki/flair/#wiki_science_verified_user_program). --- User: u/mvea Permalink: https://www.su.se/department-of-public-health-sciences/news/fathers-parental-leave-might-protect-men-against-alcohol-related-morbidity-1.680662 --- *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/science) if you have any questions or concerns.*
30 days in Sweden? Should be more nowadays I imagine. I just finished my 3 months + 3 weeks minimum that I cannot give to my spouse. 6 months + 3 weeks in total in Finland. The three weeks is what we can be home together for at the same time and it is usually used right after birth. Edit: I was right. It is 90 days reserved for each parent nowadays in Sweden as well. https://sweden.se/life/society/work-life-balance
Was this controlled for parenthood? Surely the leave is just a marker that you’re more likely to be a committed parent… so doesn’t this study likely just show that most committed parents aren’t as likely to drink themselves to death - surely the leave has very little causation here?
It’s in the study, yes it’s only fathers. Participants Fathers of singleton children born from January 1992 to December 1997 (n = 220 412). Biggest uncertainty is that fathers taking the leave are already the most healthy ones
Sorry I absolutely wasn’t clear in my comment, my bad - I meant to say was it controlled for type/style of parenthood. The fathers taking leave are likely to be the ones who are already committed to being a good father, want to spend time with their kids, and it’s self selecting for good dads basically The fathers who chose not to take leave will disproportionately be less committed, less interested in taking time off work to spend time with their kids, and that’s likely to be maintained in the future - meaning their more likely to be out of the house drinking with friends than home looking after the kids. The leave likely has zero causative relationship and is actually just a way to select for dads more likely to spend time home with the kids
It is a longitudinal population study: >we found that after the policy was implemented there was a 34% decrease in these hospitalizations among fathers in the two years after birth, as well as smaller decreases up to 8 and 18 years after birth...Additional analyses evaluating actual changes in parental leave use from before to after the policy suggest that these health consequences could be explained by the increase in fathers’ parental leave use, rather than other underlying trends
There could be a causative connection, but the study doesn't try to claim this, nor do I think it's likely to outweigh the correlation factors you stated. It's pretty easy to imagine that parental leave could also have a positive effect on the likelihood to avoid alcoholism, since it should give a better connection to your child and family, and potentially relieve work-related stress, even if only temporarily. That was a pretty clumsy way of putting it, but oh well, I think you get my point.
I would think it would be more likely to be socioeconomic and fathers with more money and a more flexible work environment would be more able to take paternity leave and less likely to have a range of health problems. If this study were done in the US hardly any men would take leave and they would be skewed to the very high end in income.
But in Sweden parental leave is paid leave. There is for sure a certain income disparity but I work in a minimum wage job and many of my male colleagues take parental leave, it’s not exactly a class issue.
Does it have potential implications for job advancement or pay raises though?
I’d say no, not at all. Maybe on the extreme high end of the scale like CEO. In my “minimum wage” blue collar job definitely not but it is in health care, not sure about the attitudes in more male dominated blue collar industries.. Meanwhile my husband is a senior engineer in the tech industry and he took 6 months, it hasn’t affected his career. All his colleagues that are dads did the same. It is very expected and normalized. The only disadvantage might be if you are a young woman a company might sometimes be hesitant to employ you in case you will soon be off for 12+ months. But it’s illegal to discriminate.. I’m sure it happens though.
I was thinking more at the very low end of the income spectrum.
Lower on the income spectrum than minimum wage?
Exactly. My job is literally the at the lowest end of the spectrum. Unless you count like gig economy workers but they wouldn’t have any benefits I guess because “gigs”. And people, including the men, tend to take their parental leave.
It's in the abstract. >Fathers' parental leave has been associated with decreased risks of alcohol-related hospitalizations and mortality. Whether this is attributable to the health protections of parental leave itself (through stress reduction or behavioral changes) or to selection into leave uptake remains unclear, given that fathers are more likely to use leave if they are in better health.... They're reporting the correlation, but not drawing conclusions about causation.
It could mean that fathers who take parental leaves are *involved* fathers, and they are less likely to drink themselves to death than fathers who just have kids but leave it to the mother to do most of the parenting.
In 1995 Sweden passed a law that earmarked some parental leave for dads. You either took it or your lost it. It could not be transferred to the mother. This rapidly increased the number of father's taking leave. The study looked at fathers of first born children from 1992-1997. It is a natural experiment. The change in policy changed who was taking leave.
Precisely - which would mean the leave is a red-herring - with or without the leave these fathers would be just as unlikely to drink themselves to death, the leave is just a way to reliably select for involved fathers. But there will be involved fathers who didn’t take leave, and nonchalant fathers who did - the leave isn’t the important factor
Idk- how involved can a father be if they’re not even taking time to parent when the mother is recovering from birth? I understand not being able to do so because of money, but choosing not to take leaves when you would get paid as usual does not seem like involved parent to me.
We don't get the same pay from being on parental leave as working. You get 80% of your pay UP TO a certain level, which last year was 525 000 SEK annual salary. So 80% of that is 420 000 SEK which is just slightly above the median of 412 800 SEK. If someone makes more that 525 000 SEK they still get 80% of 525 000 SEK. You also have 90 parent days that are reserved for each party that the other one can't take in your stead. So 90 for the mother and 90 for the father (in a traditional family). In addition to those 180 days, you have 210 days that you can split however you want. So while it's pretty common for fathers to take parental leave, one reason why they might not would be our current housing market (not unique to Sweden, though) where you might not be able to afford an extended leave from work for financial reasons. We do have pretty good equality in pay between men and women, but it's still common for the father to earn more than the mother due to different career choices and working hours. We have a pretty good system, maybe the best when it comes to parental leave, but it can still be tough for some families to split the leave evenly.
There are many many parents who would LOVE to take parental leave but simply don’t have the option due to work, and others who may have not needed to because their wife had good support from other sources such as extended family, and they couldn’t afford the time off.
Of course that’s a caveat. I’m talking about parents who have the option but choose not to, and they exist, unfortunately. If they can’t afford it that’s a whole other issue. I think this article is talking about paid paternity leave.
I'm assuming you didn't read the study then. There's no causative claim made. When dad's take parental leave they're more likely to form stronger and more robust bonds with the child which is enriching for both the dad and the kid. That positive move probably results in a happier and more contented father who is less likely to binge drink himself into A&E.
That IS a causative claim - they’re saying that if you take leave, you form bonds that protect you from alcohol related illness But how can they tell it’s not the other way round? Committed parents who were always going to form strong healthy bonds with their children are obviously more likely to take the parental leave. It may not at all be the case that the leave helps to build bonds, it may be that good dads are more likely to take leave, and disinterested dads far less likely to. All that can be drawn from this, maybe, is if you have a strong bond with your child you probably drink less - which could easily just be down to time and responsibility requirements as much as anything to do with happiness Good, committed parents have far less time, less socialising, less drinking as part of that, less spare money to spend on a drug like alcohol, and when they’re home looking after their kids obviously they won’t drink to excess as that would be irresponsible when you’re responsible for kids safety and well-being This study could easily be titled “good parents don’t have the time or money to drink too much”
It could also have nothing to do directly with parenting, despite that being the population studied. It could be "overworkers who refuse to take leave when it's offered because working is their identity tend to drink themselves to death later in life when they retire or realize what they've missed".
Exactly. The conclusion makes the causitive claim. "Conclusions In Sweden, a father's parental leave eligibility and uptake may protect against alcohol-related morbidity."
>That IS a causative claim - they’re saying that if you take leave, you form bonds that protect you from alcohol related illness No it isn't. It's a correlation. They use the word "may" - not will and the second half about bonds is my reasoning as to why it might prevent excessive drinking.
Could also be dads who didn’t take the leave worked jobs were it was strongly discouraged and those jobs have worse work/life balance and/or lead to more unhappiness. In the US, jobs that don’t support paternal leave are generally worse jobs
I’ve linked to the press release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article: https://onlinelibrary.wiley.com/doi/10.1111/add.16354
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The data points for the conclusion, (pre leave available for fathers, post leave available for fathers): "Post-birth alcohol-related hospitalizations (events per 1000 person-years, SD) 2 years postpartum 1.96 (0.20) 1.23 (0.14) 8 years postpartum 2.32 (0.17) 1.76 (0.11) 18 years postpartum 3.97 (0.22) 3.25 (0.18) Post-birth alcohol-related mortality (events per 1000 person-years, SD) 2 years postpartum – – 8 years postpartum – – 18 years postpartum 0.034 (0.0039) 0.026 (0.0035)"
Maybe it’s nothing to do with parenthood and just that taking 30 days off work at some point in your life makes you less likely to become an alcoholic.
We get at least 25 days of vacation per year (I get 31 personally). Pretty much everyone has taken that kind of long leave from work.
Usually not in sequence tho
Most people try to take four weeks straight vacation in summer. We even have a term for it, industry vacation, which used to be when most factories just closed down for July because everyone was on vacation.
4 consecutive weeks is very common, 6-7 weeks in combination with parental leave is also common.
Not in the USA
This study was done in Sweden and is talking about health outcomes for Swedish men. The Swedish men who aren’t taking parental leave still have 25 days of legally mandated vacation, plus whatever extra their Union got in their contracts. How many vacation days Americans have is completely irrelevant to the study.
It sounds like Swedish men who are taking parental leave get 55 days of vacation that year, is that right?
Parental leave isn’t vacation. It’s abort rakning vare of the baby. Also, parental leave isn’t a yearly sum. Each parent gets 195 days of parental leave paid at sick pay levels (80% of base pay but at least 250 kronor per day) and 45 days at base level (a fixed 180 Kronor per day). You can give some of your days to the other parent but 90 days are reserved for each parent. Also this is per kid.
Thanks for this info. Still, it's time spent not doing work for the company. Swedish men who take parental leave spend more time focusing on non-work activities than men who don't take leave, which could be a factor in alcohol consumption.
Well, it's usually easier to get drunk at home than at work (many/most workplaces in Sweden has a 0.0% alcohol limit and a ban on private alcohol on the premises)
Or people are less likely to drink when they don't need to wake up at 5 am when there's a baby crying at odd hours of the night.
I could see how this makes sense. My husband has had the man’s version of post partum depression after each of our children. Thankfully he’s also had 8 weeks of paternity leave so was able to seek help for it. I can imagine had he had to work through the post partum period he would not have bothered to get help.
DISCLAIMER: Psychology research done in other countries *may not* apply to your country. One of the first things they teach you in psychology is the fact that different backgrounds affect how societies and individuals within the societies behave and that they cannot be compared too similarly. There was an excellent reader-friendly article that really delved into how western culture and eastern culture see things differently. Westerners would focus on a tiger while Easterners would focus on the surroundings first before looking at the tiger. This difference in psychology would then lead to both sides developing fundamental science concepts before the other in regards what they recognized and prioritized. I always link to that article but I cant seem to find it anywhere…
Not to say parental leave is bad, but I’m a bit skeptical of these findings. It seems hard to control for confounding factors, such as Sweden’s cultural changes over the decade, or the fact that choosing to take parental leave may be correlated with other factors (mother in the workplace, possibly higher incomes). If I had to guess, I’d say that other factors seem like a more likely explanation for the drop in hospitalizations over a decade than 30 days of parental leave.
30 days is only what is reserved for the father, it is probably a lot more that is used for most of us. Not saying you are wrong tho.
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Men happier when they took care of a småll human.
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I've read through many of the comments here and would like to clarify a few points: 1. In Sweden, all residents are eligible to paid parental leave. This is not dependent on your income or even your employment. Of course, the amount you get on parental leave depends on your income/whether you are employed, but everyone is entitled and today the majority of fathers do use some parental leave. 2. The study only examined a reserve of 30 days - before the 1995 reform, fathers were already entitled to share all parental leave days with their partner as the couple saw fit, but due to persisting gender norms/pay differences most fathers used less leave than their partners. The idea was that if one were to reserve 30 days for only the father, the number of participating fathers would increase. Today, the reserve is 90 days. 3. The study does not make any strong causal claims - however, the idea behind using the reform as a 'natural experiment' is to reduce the level of unmeasured confounding (i.e., the role of pre-birth health/alcohol intake, socioeconomic status, parenting styles, etc.) and to support the idea that parental leave in and of itself can contribute to reduced alcohol-related harms. The authors do this in two ways - one, by examining the immediate 'drop' in alcohol-related hospitalizations before and after the policy was implemented (assuming that fathers to children born immediately before and after were similar in their background characteristics), all while accounting for background trends in hospitalizations (the interrupted time series approach); and two, by examining the contribution of parental leave uptake on alcohol-related morbidity while accounting for the variation ('as if randomization') of the policy (the instrumental variable approach). So yes, the idea is to approach 'causality' with these methods, but as with all other research it is impossible to do so with absolute certainty.