I recently wrote to Dame Sally Davies, Chief Medical Officer of England and to the British government, asking her for the basis of her statement to the BBC regarding MMR: "It's a safe vaccination - we know that", and was a lucky enough to receive a reply (letter of 12 November, from which I extract):
Specifically in relation to whether MMR vaccines may be a cause of autism, a substantial body of population-based research has found no evidence to suggest a causal association. This evidence (not just for MMR, but other types of vaccine) is available for review in the published medical literature, and was summarised in a meta-analysis in 2014 which is free to download (https://www.sciencedirect.com/science/article/pii/S0264410X14006367?via%3Dihub).
In relation to vaccine safety monitoring more generally, I can assure you that systems are in place to keep safety under review. This includes continual review of suspected adverse reaction reports (such as those submitted through the Yellow Card Scheme), evaluation of GP and hospital-based health records linked to immunisations, review of worldwide data and close collaboration with international health authorities.
It is noteworthy that the "meta-analysis" by Luke E Taylor is identical to the one cited by Thomas Insel to a US Congressional committee in 2014, but it constitutes no more than a bureaucratic fig-leaf. Dame Sally - who is the UK's leading government adviser on medical matters - ought to be able to do a lot better than this if every child is to be subjected to these products. It is, if anything, a rather naive response citing a shallow collection of studies which were published under political pressure decades after the policy was introduced. I have since attempted a conscientious and detailed reply:
21 November 2018
Dear Dame Sally,
Thank you for your letter of 12 November. I would point out that though you are quite right I am concerned about the rise in autism I specifically asked about the evidence base for MMR safety. That said it is reasonable to point out autism for a whole host of reasons is a much more serious problem in modern Britain (and elsewhere) than measles. When the DHSC last surveyed this problem in 2004-5 the overall ASD rate among school children was ~1% which was 5 times higher than the rate for those young people born between 1984-8 mostly before MMR was introduced, as reported in the equivalent 1999 survey. Since then your department has neglected to look at the issue (apart from a couple of failed adult autism surveys) as everything manifestly got worse, year on year [1,2].
As it is, a recent survey carried out by the Department of Health in Northern Ireland showed that the rate had risen from 1.2% in 2009 to 2.9%, while in Belfast it was as high as 4.7%. Moreover, 60% are educational Stage 5 , ie the most severe level of disability, so these are not cases that could previously have been missed because somehow subliminal. Educational data from across the nation and reports of collapse in educational services in the media testify that Northern Ireland is not an isolated case, but just better documented .
Regarding the meta-review by Taylor 'Vaccines are not associated with autism'  which you cited I note that there are just six MMR related studies included all of which have major problems. Three of the studies show apparent protective effect of MMR vaccines against autism (Madsen 8% , Smeeth 14% or 22%  and Mrozek-Budzyn 83%!!! ) which suggests bias. Of the Madsen paper Cochrane 2005 warned :
"The follow up of diagnostic records ends one year (31 Dec 1999) after the last day of admission to the cohort. Because of the length of time from birth to diagnosis, it becomes increasingly unlikely that those born later in the cohort could have a diagnosis"
It remains troubling that as with a number of studies from this Danish group the co-ordinator on behalf of US Centers for Diseases Control, Poul Thorsen, is wanted for financial fraud from the CDC, though not extradited to the US now after nearly 8 years .
Of the De Stefano paper Cochrane commented :
“The conclusion, however, implied bias in the enrollment of cases which may not be representative of the rest of the autistic population of the city of Atlanta, USA where the study was set.”
And indeed in 2014 the paper was repudiated by one of the leading authors, William Thompson :
“I regret that my coauthors and I omitted statistically significant information in our 2004 article published in the journal Pediatrics. The omitted data suggested that African American males who received the MMR vaccine before age 36 months were at increased risk for autism. Decisions were made regarding which findings to report after the data were collected, and I believe that the final study protocol was not followed.”
The study by Smeeth  is compromised by its patchy data source, the General Practice Research Database where the autism rate represented is perhaps only one tenth of cases diagnosed . Cochrane commented :
“In the GPRD - based studies (Black 2003; Smeeth 2004) the precise nature of controlled unexposed to MMR and their generalisability was impossible to determine…”
It remains problematic whether the unvaccinated in this study were genuinely unvaccinated.
Of the Uchiyama study  Cochrane commented :
“The cohort study of Uchiyama 2007 was potentially affected by a different type of bias, considering that the participants were from a private clinic and that definitions of applied Autistic Spectrum Disorders (ASD) diagnosis and of methods used for ASD regression ascertainment were not clearly reported.”
And the Uno study  will suffer from similar issues since the cases came from the same clinic. Moreover, in both instances the studies were far too small (904 persons and 413) to necessarily provide any clear result even if they had been better controlled.
Nor can the Taylor meta-analysis  cover up the entire absence of pre-marketing studies. In 1988-9 when the British government was persuaded to introduce Pluserix, MMR2 and Imravax there were no safety studies at all, and successive governments have been forced into the defence of a policy which they had embarked on without safety evidence.
As to the robustness of the yellow card reporting system I note the recent correspondence in the columns of BMJ On-Line regarding monitoring of Pandemrix vaccine from Wendy E Stephen and Clifford G Miller , which has serious implications for how the MHRA monitor all products. The MHRA has, of course, the ultimate conflict of being entirely funded by the manufacturers. It may be mentioned that in 1992 the Pluserix and Imravax vaccines were withdrawn not apparently by the British Government concerned about patient safety but by the manufacturers catching the government on the hop .
We are confronting a catastrophic situation among our young people with chronic illness replacing infectious illness as the main issue and cost to the state, and laying the emphasis on infectious diseases (with endless hate campaigns in the media against critics labelled “anti-vaxxers”) is a distraction, and a distortion of policy. It would be unfortunate if ministers were being advised about the safety of the programme on such a threadbare and inadequate basis. Re-examining the policy is both essential and urgent.
 John Stone, ‘Response to David Oliver I (The Indisputable Rise in Autism)’, BMJ Rapid Responses 28 August 2018, https://www.bmj.com/content/362/bmj.k3596/rr-12
 John Stone, ‘What about autism?’ BMJ Rapid Responses, 21 August 2018, https://www.bmj.com/content/362/bmj.k3596/rr-0
 Information Analysis Directorate 'The Prevalence of Autism (including Asperger Syndrome) in School Age Children in Northern Ireland 2018', published 10 May 2018, https://www.health-ni.gov.uk/sites/default/files/publications/health/asd-children-ni-2018.pdf
 Responses to Viner RM, 'NHS must prioritise health of children and young people', https://www.bmj.com/content/360/bmj.k1116/rapid-responses
 Luke E Taylor et al, ‘Vaccines are not associated with autism: An evidence-based meta-analysis of case-control and cohort studies’, Vaccine 2014, https://autismoevaccini.files.wordpress.com/2014/05/vaccines-are-not-associated-with-autism.pdf
 Madsen et al, ‘A Population-Based Study of Measles, Mumps, and Rubella Vaccination and Autism’, NEMJ 2002, https://www.nejm.org/doi/full/10.1056/NEJMoa021134
 Smeeth et al, ‘MMR vaccination and pervasive developmental disorders: a case-control study.’ Lance 2004, https://www.ncbi.nlm.nih.gov/pubmed/15364187
 Mrozek-Budzyn et al, ‘Lack of association between measles-mumps-rubella vaccination and autism in children: a case-control study.’ Pediatric Infectious Diseases Journal 2010, https://www.ncbi.nlm.nih.gov/pubmed/19952979
 Demicheli et al, ‘Vaccines for measles, mumps and rubella in children.’, Cochrane Database Syst Rev. 2005 Oct 19;(4):CD004407.
 Office of Inspector General, US Department of Health and Human Services, Fugitive Profiles, https://oig.hhs.gov/fraud/fugitives/profiles.asp
 John Stone, ‘An old story: the GPRD does not provide credible autism data’ 11 February 2014 https://bmjopen.bmj.com/content/3/10/e003219.responses
 Uchiyama et al, ‘MMR-vaccine and regression in autism spectrum disorders: negative results presented from Japan.’ J Autism Dev Disord. 2007 Feb;37(2):210-7.
 Demicheli et al, ‘Vaccines for measles, mumps and rubella in children.’, Cochrane Systematic Review - Intervention Version published: 15 February 2012, https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004407.pub3/full
 Uno et al, ‘The combined measles, mumps, and rubella vaccines and the total number of vaccines are not associated with development of autism spectrum disorder: the first case-control study in Asia’, Vaccine. 2012 Jun 13;30(28):4292-8. doi: 10.1016/j.vaccine.2012.01.093. Epub 2012 Apr 20.
 Responses to Godlee, ‘A tale of two vaccines’ BMJ 2018, https://www.bmj.com/content/363/bmj.k4152/rapid-responses
 Report, BMJ 26 September 1992, https://www.bmj.com/content/305/6856/777
When your government, the BBC or the mainstream media tell you that MMR is safe, this the best that the British government can do. After three decades of pure bluster they need to go back to the drawing board.