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Read-Do and Do-Confirm checklists illustration: examples of a Dinner party fail and an Expedition checklist

Two types of checklists: Read-Do, Do-Confirm

I always considered a checklist, a checklist, so I was interested to learn the distinction between two types of checklists: Read-Do and Do-Confirm. A Read-Do checklist might be prepared in advance for several potential possibilities. You check off the tasks as you do them, like following a new cooking recipe. They may be geared towards helping people understand what they should be doing and in what order and helping them remember key steps in unusual or unplanned scenarios. So, for example, if a plane develops a particular type of rare fault, such as an engine failure, a Read-Do checklist could be pulled out for that scenario. The pilot and crew can use it to make the most of others' past experiences and failures. Even with training, given the situation's relative rarity, and especially if a serious situation might interfere with normal thinking, a Read-Do checklist helps steer the crew to safe outcomes without relying solely on training and memory. The calm security and simplicity of steps of a checklist can be just what's needed. A Do-Confirm checklist is more of an aid to memory to make sure nothing gets missed. It's a safety net for normal operation catching lapses in memory. In principle, we know what to do, so we run through those steps from experience and memory and use the Do-Confirm checklist at a designated pause point to ensure we didn't miss anything. The WHO Safe Surgery checklist has helped save 1,000s of lives. Because a simple checklist can never account for every unexpected occurrence in complex environments—for example, healthcare, aviation, building a skyscraper, or software projects—both checklist types can benefit from items that require a communication step. An item can just be to ensure that all those with the relevant knowledge have discussed things. It's a simple and powerful way to improve outcomes across a wide range of unexpected scenarios. I learned about the simple power of checklists, the two types, and the resistance to adopting them—from Atul Gawande's, The Checklist Manifesto: How to get Things Right.…I always considered a checklist, a checklist, so I was interested to learn the distinction between two types of checklists: Read-Do and Do-Confirm. A Read-Do checklist might be prepared in advance for several potential possibilities. You check off the tasks as you do them, like following a new cooking recipe. They may be geared towards helping people understand what they should be doing and in what order and helping them remember key steps in unusual or unplanned scenarios. So, for example, if a plane develops a particular type of rare fault, such as an engine failure, a Read-Do checklist could be pulled out for that scenario. The pilot and crew can use it to make the most of others' past experiences and failures. Even with training, given the situation's relative rarity, and especially if a serious situation might interfere with normal thinking, a Read-Do checklist helps steer the crew to safe outcomes without relying solely on training and memory. The calm security and simplicity of steps of a checklist can be just what's needed. A Do-Confirm checklist is more of an aid to memory to make sure nothing gets missed. It's a safety net for normal operation catching lapses in memory. In principle, we know what to do, so we run through those steps from experience and memory and use the Do-Confirm checklist at a designated pause point to ensure we didn't miss anything. The WHO Safe Surgery checklist has helped save 1,000s of lives. Because a simple checklist can never account for every unexpected occurrence in complex environments—for example, healthcare, aviation, building a skyscraper, or software projects—both checklist types can benefit from items that require a communication step. An item can just be to ensure that all those with the relevant knowledge have discussed things. It's a simple and powerful way to improve outcomes across a wide range of unexpected scenarios. I learned about the simple power of checklists, the two types, and the resistance to adopting them—from Atul Gawande's, The Checklist Manifesto: How to get Things Right.

9 Jul 2023

Complaining at the weather

It's easy to want to complain at the weather. The trouble is, it doesn't have any effect on it.…

2 Jul 2023

Siphon

The siphon, or syphon, is a simple device that uses only a tube to seemingly pump water from a higher spot to a lower one. It's ingenious because once you start the siphon by filling the pipe to below the height of the upper reservoir level, it will continue draining the water, pulling it over the hump and towards the collection below without further help. Most of us use siphons several times daily, as there are often two at work in the standard toilet. Sometimes there's one in the flush mechanism—one push of the handle to start the siphon drains the water from the reservoir until it runs out. And you can flush a toilet using the second siphon by pouring enough water directly into the bowl to push the water over the bend in the pipe to start it— think how the water drains by itself almost completely before filling up to the level of the bend once again. It's a clever way to power a toilet flush with just the press of a button or turn of a handle. They also minimise leaks and control the flow by running the water uphill. We set up a greywater siphon to drain water from the bath and showers to a water butt in the garden. To get it started, we connected the end of the hose in the garden to a tap and ran water back up the hose until it shot out the top. Then, dipping it in the water, turning off the tap, and putting the end in the water butt, like magic, the siphon pulls water out of the bath until it's empty. Surprisingly, a few effects are at work in a siphon, and its mechanism is debated. They can be made to work in a vacuum and even spray liquid upwards with the right setup. I read that it is from the ancient Greek siphōn meaning a tube or pipe, often for drawing wine from a cask—that would be a decent situation to start the siphon by sucking on the end.…The siphon, or syphon, is a simple device that uses only a tube to seemingly pump water from a higher spot to a lower one. It's ingenious because once you start the siphon by filling the pipe to below the height of the upper reservoir level, it will continue draining the water, pulling it over the hump and towards the collection below without further help. Most of us use siphons several times daily, as there are often two at work in the standard toilet. Sometimes there's one in the flush mechanism—one push of the handle to start the siphon drains the water from the reservoir until it runs out. And you can flush a toilet using the second siphon by pouring enough water directly into the bowl to push the water over the bend in the pipe to start it— think how the water drains by itself almost completely before filling up to the level of the bend once again. It's a clever way to power a toilet flush with just the press of a button or turn of a handle. They also minimise leaks and control the flow by running the water uphill. We set up a greywater siphon to drain water from the bath and showers to a water butt in the garden. To get it started, we connected the end of the hose in the garden to a tap and ran water back up the hose until it shot out the top. Then, dipping it in the water, turning off the tap, and putting the end in the water butt, like magic, the siphon pulls water out of the bath until it's empty. Surprisingly, a few effects are at work in a siphon, and its mechanism is debated. They can be made to work in a vacuum and even spray liquid upwards with the right setup. I read that it is from the ancient Greek siphōn meaning a tube or pipe, often for drawing wine from a cask—that would be a decent situation to start the siphon by sucking on the end.

25 Jun 2023

Cake wreck

Cake Wrecks is the blog and book of when professional cakes go hilariously wrong, by Jen Yates. But a cake wreck is also a useful metaphor for how easy it can be to misinterpret instructions—often by simply taking something literally when it was expected to be interpreted. Examples from Jen's collection include a smart-looking cake with "Nothing" written across the front, a graduation cake with "I want sprinkles" next to a graduation cap, or a cake sporting a full "Happy birthday on a gluten-free cake." If you haven't seen them, you could do much worse than look some up now. It's easy to laugh at these examples, but it's also easy to find real examples in day-to-day work. I learned about cake wrecks from Jeff Patton's excellent book User Story Mapping. He gives cake wrecks as an all too common example of communication in software development. For example, a user story or specification for a feature is written and passed on to developers who, in the absence of other communication and with perhaps cultural or status barriers, may carefully build exactly what is written rather than what the writer intended. Cake wrecks are funny and silly—except if it was for your special occasion—but mistakes in projects are expensive in time, money and relationships and are worth avoiding. The recipe for avoiding a cake wreck is, in principle, simple: Communicate more Don't assume that what you see is what someone else will see Share richly Use stories and specifications as tools for talking about what's needed and not as equivalents of it Create a safe space for everyone to question what they don't understand or don't agree with Give everyone the 'why' behind a project and autonomy and flexibility to suggest other ways to meet the goal Check in during a project and adjust as needed Apron?…Cake Wrecks is the blog and book of when professional cakes go hilariously wrong, by Jen Yates. But a cake wreck is also a useful metaphor for how easy it can be to misinterpret instructions—often by simply taking something literally when it was expected to be interpreted. Examples from Jen's collection include a smart-looking cake with "Nothing" written across the front, a graduation cake with "I want sprinkles" next to a graduation cap, or a cake sporting a full "Happy birthday on a gluten-free cake." If you haven't seen them, you could do much worse than look some up now. It's easy to laugh at these examples, but it's also easy to find real examples in day-to-day work. I learned about cake wrecks from Jeff Patton's excellent book User Story Mapping. He gives cake wrecks as an all too common example of communication in software development. For example, a user story or specification for a feature is written and passed on to developers who, in the absence of other communication and with perhaps cultural or status barriers, may carefully build exactly what is written rather than what the writer intended. Cake wrecks are funny and silly—except if it was for your special occasion—but mistakes in projects are expensive in time, money and relationships and are worth avoiding. The recipe for avoiding a cake wreck is, in principle, simple: Communicate more Don't assume that what you see is what someone else will see Share richly Use stories and specifications as tools for talking about what's needed and not as equivalents of it Create a safe space for everyone to question what they don't understand or don't agree with Give everyone the 'why' behind a project and autonomy and flexibility to suggest other ways to meet the goal Check in during a project and adjust as needed Apron?

18 Jun 2023

The ring-segment illusion

Yes, the two train track pieces are the same lengths. I know this because we have a basket of toy train tracks, and I took two identical curves and lined them up for the outline of this sketch. But it's easy to be fooled and think the one at the top is shorter than the one at the bottom. While there may be other factors to help explain the ring-segment illusion, a common one is that our brains compare the short inner side of the top track against the longer outer side of the lower track leading us to believe the top one is shorter. Aligning the top track to the outer left point of the lower track enhances the illusion by increasing the horizontal contrast. I like the ring-segment illusion as the name for it. It's also known as the Jastrow illusion after the Polish-American psychologist Joseph Jastrow, also known for the ambiguous figure of the rabbit-duck, who published a tapered version of the ring-segment illusion. In his paper, he gives a related example of how a square sitting on a point can look larger than one sitting on a side as we subconsciously compare the longer diagonal length with the shorter side length. You can test that in the sketch. More sketched illusions…Yes, the two train track pieces are the same lengths. I know this because we have a basket of toy train tracks, and I took two identical curves and lined them up for the outline of this sketch. But it's easy to be fooled and think the one at the top is shorter than the one at the bottom. While there may be other factors to help explain the ring-segment illusion, a common one is that our brains compare the short inner side of the top track against the longer outer side of the lower track leading us to believe the top one is shorter. Aligning the top track to the outer left point of the lower track enhances the illusion by increasing the horizontal contrast. I like the ring-segment illusion as the name for it. It's also known as the Jastrow illusion after the Polish-American psychologist Joseph Jastrow, also known for the ambiguous figure of the rabbit-duck, who published a tapered version of the ring-segment illusion. In his paper, he gives a related example of how a square sitting on a point can look larger than one sitting on a side as we subconsciously compare the longer diagonal length with the shorter side length. You can test that in the sketch. More sketched illusions

11 Jun 2023

Fortnightly

What does biweekly mean to you? How about bimonthly or biannually? While each of us will have our own, perhaps unambiguous, reaction to it, the word biweekly is interpreted as "twice a week" or "once every two weeks." I know this from personal experience of confusing people en-masse. The dictionary even carefully, if unhelpfully, defines it as meaning either. It's a strange quirk of the English language. But it's so handy, what to do? An excellent, concise solution is the word fortnightly. Fortnightly has the helpful unambiguous quality that it means "once every fortnight," so "once every two weeks." And it's also just one word. If something happens "two times a week," I think you need to spell it out or use "twice a week" or perhaps "every Monday and Thursday." Or perhaps semi-weekly might give you some mileage. The same source of confusion applies to the words bimonthly and biannually—to be sure of being understood correctly, it's best to avoid them. Phrases like "every second month," "every two months," "twice a month," or "two times each year" are helpful here. Ambiguity in how we talk about time is also illustrated in some of my favourite research done by Lera Boroditsky. For example, if I say, "The meeting on Wednesday has been moved forward by two days," when is the meeting now? It turns out that people are split on whether the meeting is now on Monday or on Friday. And I remember a fascinating example of the Kuuk Thayore aboriginal people in Australia who don't use words like left and right, and instead, always use the cardinal directions like north, south, east and west—"Oh, there's an ant on your southwest leg". There's a taster in her talk, How Language Shapes the Way we Think.…What does biweekly mean to you? How about bimonthly or biannually? While each of us will have our own, perhaps unambiguous, reaction to it, the word biweekly is interpreted as "twice a week" or "once every two weeks." I know this from personal experience of confusing people en-masse. The dictionary even carefully, if unhelpfully, defines it as meaning either. It's a strange quirk of the English language. But it's so handy, what to do? An excellent, concise solution is the word fortnightly. Fortnightly has the helpful unambiguous quality that it means "once every fortnight," so "once every two weeks." And it's also just one word. If something happens "two times a week," I think you need to spell it out or use "twice a week" or perhaps "every Monday and Thursday." Or perhaps semi-weekly might give you some mileage. The same source of confusion applies to the words bimonthly and biannually—to be sure of being understood correctly, it's best to avoid them. Phrases like "every second month," "every two months," "twice a month," or "two times each year" are helpful here. Ambiguity in how we talk about time is also illustrated in some of my favourite research done by Lera Boroditsky. For example, if I say, "The meeting on Wednesday has been moved forward by two days," when is the meeting now? It turns out that people are split on whether the meeting is now on Monday or on Friday. And I remember a fascinating example of the Kuuk Thayore aboriginal people in Australia who don't use words like left and right, and instead, always use the cardinal directions like north, south, east and west—"Oh, there's an ant on your southwest leg". There's a taster in her talk, How Language Shapes the Way we Think.

4 Jun 2023

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