News that 34 people have been killed in Cairo today raises Egypt's death toll - but to what number? Since nationwide protests began, various figures have been circulated. This is our attempt to gauge the true cost of the conflict so far
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Death counts matter. They provide an indication of how violent the protests and subsequent crackdowns are. But in a country of more than 80 million people, counting numbers is difficult at the best of times. So the Guardian's data team are attempting to collect, verify and share more reliable numbers - and we need your help.
Where are the totals?
Headlines today claim anywhere between 30 and 42 dead. The more pragmatic state "several", "dozens" or "at least" before providing a number. The problem is, these are referring to just one incident - a shooting outside the headquarters of the Republican Guard in Cairo earlier today.
They fail to tell us anything about how many Egyptians across the country have been killed or injured since violence began in June. Journalists and human rights activists have been reluctant to share those totals simply because they may not be reliable.
Those wanting to report on violence in Egypt might find themselves confronted with a choice: cite the total number of dead and injured provided by Egypt's ministry of health or else sidestep total figures altogether, writing on a case-by-case basis using more reliable reports.
Since Friday, Guardian Data attempted to overcome this challenge by drawing together various reports and putting them in a downloadable spreadsheet.
Using agency, news and NGO sources we have counted at least 100 dead and 1,053 injured in clashes across Egypt since 23 June 2013. We know there are fatal incidents we have not yet included and will regularly update this figure.
Using a spreadsheet means we can attempt to ensure that events aren't duplicated, which would result in overestimating casualty figures. Information on the location and date of incidents starts to build up an important picture of how widespread and how fatal the clashes in the country have been.
The sources are not equally reliable. For example, Human Rights Watch has staff in the country who identify every individual mentioned in their casualty figures by name and age. By contrast, some press reports use the state news agency MENA to provide estimates.
We have attempted to use the best available sources and be transparent about their reliability. That means that we should be able to eventually share a conservative and an upper estimate from our totals.
Our obstacles
While this open data is a critical attempt to draw together disparate reporting, it is far from perfect. Here are some of the issues which we face:
• Snapshots
Individuals who have been counted among the wounded on Friday may have since passed away. But accounts which count the dead often only include immediate casualties. Those who die as a result of their wounds may go uncounted in the death toll.
• Place names
Arabic place names have not been transliterated consistently. While there may be consensus about the spellings of Alexandria, Luxor and Cairo, places like المنوفية may be written as Menoufia, Monufiya, Minufiyah, Minoufiya or countless other variants. To add to the complication, the location mentioned in the report might refer to a district, a city or a governorate. That increases the chances of error; if we don't notice that a report mentioning Al Arish is the same incident as another article which discusses events in the North Sinai (because Al Arish is a city in North Sinai) they may be counted twice.
• Injured
The number of wounded is often a weak estimate. When hundreds of thousands of protesters take to the streets, as Morsi's opponents did on Sunday, it is very difficult to know how many suffered injuries. Often staff from nearby hospitals are relied upon to provide numbers - which may only reflect the most serious injuries. Knowing that hospitals are likely to be overrun, protesters with lesser injuries may instead go home to dress their wounds and would remain uncounted.
What you can do
Despite these challenges, our spreadsheet so far has been extremely helpful. With powers in the country changing so rapidly in the past month, it is important to provide a check on government sources which may have an interest in over- our underestimating the numbers. Our running total suggests that the statistics being released from the ministry of health are reliable.
Most importantly, we know what we don't know. Several locations have been mentioned in reports but with no further detail about the incident. For example, an AFP report last week says:
Anti-Morsi protests were held in the coastal city of Alexandria, the Nile Delta cities of Mansura, Menuf, Tanta and Mahalla, the canal cities of Suez and Port Said and in the president's hometown of Zagazig.
Subsequent reports mention violence in these locations but provide no numbers on dead and injured. You can help us count the real cost of Egypt's conflict so far by:
• Looking at the 'to check' tab in the spreadsheet below. If you have seen a source that provides numbers on the dead and wounded in Damanhour, Mokattam or any of the other locations mentioned, please share a link that source
• Sharing your views on whether the sources we are using so far are reliable
• Letting us know if we have inadvertently double counted anything or if there is anything we've missed
Ways that you can get in touch
• Email us at data@guardian.co.uk
• Tweet us
• Contact us on Facebook
• You can also share your own testimonials from Egypt with GuardianWitness
• Post a comment below
Download the data
• DATA: download the full spreadsheet